PFAS

Curr Allergy Asthma Rep. 2025 May 21;25(1):25. doi: 10.1007/s11882-025-01206-9.

ABSTRACT

PURPOSE OF REVIEW: The frequency of natural disasters, other extreme weather events, and downstream emissions of emerging contaminants is increasing. One category of health outcome that is now experiencing increased prevalence due to these environmental threats is respiratory disease, specifically asthma and allergies; though a review summarizing current knowledge and research gaps has not been synthesized on this topic in recent years despite growing evidence.

RECENT FINDINGS: We identified recent literature that connects allergy/asthma with environmental events that are increasing in prevalence alongside natural disasters and other extreme weather events, including algal blooms, floods, heat stress, wildfires, and thunderstorms. Coinciding emissions of per-and polyfluoroalkyl substances (PFAS) and microplastics (MPs) are also discussed as downstream outcomes of these environmental events. Available evidence ranged according to environmental event/stressor type, with over 50 papers identified as relevant to this research scope in the last five years. Narrative synthesis of these papers highlighted exposure-disease linkages for stressors related to natural disasters, other extreme weather events, and downstream emissions of emerging contaminants with pulmonary asthma and allergy outcomes. Underlying biological mechanisms are beginning to be elucidated and include widespread inflammation in the lungs and changes in immune cell signaling and function across the pulmonary system. Take home points in this review pave the way for future investigations to better understand the impacts of these environmental events amongst the complex milieu of threats becoming increasingly prevalent worldwide.

PMID:40397190 | DOI:10.1007/s11882-025-01206-9

Environ Sci Process Impacts. 2025 May 21. doi: 10.1039/d4em00703d. Online ahead of print.

ABSTRACT

Paired surface wastewater samples from seven wastewater treatment plants (WWTPs) in Kaohsiung, Taiwan, were analyzed to quantify environmental PFAS loadings. Seventeen per- and poly-fluoroalkyl substances (PFASs) were analyzed, whereby WWTPs 1-4, treating domestic discharges, exhibited relatively low concentrations of 10.5-46.8 ng L^-1. WWTP 5, handling mixed domestic and light industrial wastewater, had moderate levels of 45.7-102.3 ng L^-1. WWTPs 6 and 7, which process heavy industrial discharges, recorded the highest PFAS concentrations of up to 2790 ng L^-1 and 4290 ng L^-1, respectively. The dominant PFAS compounds varied by facility: perfluoropentanoic acid (PFPeA) and 6:2 fluorotelomer sulfonate (6:2 FTS) in WWTPs 1-4, 6:2 FTS and perfluorooctanesulfonic acid (PFOS) in WWTPs 5, 6, and 7. Principal Component Analysis (PCA) confirmed that reverse osmosis (RO) effectively reduced PFAS concentrations, while conventional treatment processes lacked significant degradation capability. Three WWTPs (5-7) in Kaohsiung's heavily industrialized southern region had effluent PFAS levels exceeding the EPA lifetime health advisory limit of 70.0 ng L^-1. These findings highlight the urgent need for advanced treatment technologies and provide essential data to support Taiwan EPA's PFAS management regulations in WWTPs.

PMID:40396405 | DOI:10.1039/d4em00703d

Curr Allergy Asthma Rep. 2025 May 21;25(1):25. doi: 10.1007/s11882-025-01206-9.

ABSTRACT

PURPOSE OF REVIEW: The frequency of natural disasters, other extreme weather events, and downstream emissions of emerging contaminants is increasing. One category of health outcome that is now experiencing increased prevalence due to these environmental threats is respiratory disease, specifically asthma and allergies; though a review summarizing current knowledge and research gaps has not been synthesized on this topic in recent years despite growing evidence.

RECENT FINDINGS: We identified recent literature that connects allergy/asthma with environmental events that are increasing in prevalence alongside natural disasters and other extreme weather events, including algal blooms, floods, heat stress, wildfires, and thunderstorms. Coinciding emissions of per-and polyfluoroalkyl substances (PFAS) and microplastics (MPs) are also discussed as downstream outcomes of these environmental events. Available evidence ranged according to environmental event/stressor type, with over 50 papers identified as relevant to this research scope in the last five years. Narrative synthesis of these papers highlighted exposure-disease linkages for stressors related to natural disasters, other extreme weather events, and downstream emissions of emerging contaminants with pulmonary asthma and allergy outcomes. Underlying biological mechanisms are beginning to be elucidated and include widespread inflammation in the lungs and changes in immune cell signaling and function across the pulmonary system. Take home points in this review pave the way for future investigations to better understand the impacts of these environmental events amongst the complex milieu of threats becoming increasingly prevalent worldwide.

PMID:40397190 | DOI:10.1007/s11882-025-01206-9

Environ Health Perspect. 2025 May 21. doi: 10.1289/EHP16980. Online ahead of print.

ABSTRACT

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) have been associated with numerous deleterious health outcomes including liver damage. However, whether exposure to PFAS is associated with liver cancer risk remains unclear.

METHODS: We conducted a matched nested case-control study among 12 prospective cohort studies located in the United States. Pre-diagnostic PFAS, namely perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorohexanesulfonate (PFHxS), were measured from blood samples among 853 individuals who developed liver cancer and 853 matched control participants. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using multivariable-adjusted conditional logistic regression for liver cancer risk by study-specific quartiles of concentrations and per 90^th vs. 10^th percentile incremental increase.

RESULTS: In the main multivariable-adjusted model, circulating PFOS, PFOA, and PFHxS levels were not associated with liver cancer risk (OR per 90^th vs. 10^th percentile increase: 1.00, 95% CI: 0.79-1.28; 0.92, 0.73-1.15; and 0.95, 0.75-1.21, respectively). However, when analyses were stratified by sex, PFOA concentrations were positively associated with liver cancer risk in males (OR per 90^th vs. 10^th percentile increase: 1.62 95% CI:1.07-2.45), whereas an inverse association was observed amongst females (OR per 90^th vs. 10^th percentile increase:0.68, 0.50-0.92; p-interaction=0.005). Analyses separating liver cancer subtypes, hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma, showed no evidence of heterogeneity, although associations were stronger but not significant for HCC. No evidence of interaction was observed by time to diagnosis, time period of blood draw, body mass index, alcohol intake, ethnicity, or diabetes status.

CONCLUSIONS: In the largest study to date, none of the measured circulating PFAS were associated with liver cancer risk; however, PFOA associations appeared to differ by sex and further research is needed to explore these apparent differences by sex. https://doi.org/10.1289/EHP16980.

PMID:40397817 | DOI:10.1289/EHP16980

Crit Rev Toxicol. 2025 May 20:1-48. doi: 10.1080/10408444.2024.2446453. Online ahead of print.

ABSTRACT

This paper examines widely held beliefs about the six per- and polyfluoroalkyl substances (PFAS) addressed in the final U.S. Environmental Protection Agency's (EPA) rule on PFAS in drinking water (e.g., the Maximum Contaminant Levels - MCLs). Based on our understanding of the scientific literature and the comments submitted by stakeholders regarding the EPA's regulation that was promulgated in April 2024, we identified 15 misconceptions that had a weak scientific foundation. These are now memoralized in the MCLs for the six PFAS but remain debated due to ongoing ambiguous research findings. Many critics of the MCLs found the EPA's systematic review of the published relevant information, particularly the toxicology of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), to be inadequate. The following seven views are among the most important. First, the EPA asserted that the toxicology of these six chemicals was poorly understood and lacked sufficient data to determine a safe daily intake level for chronic health effects; nonetheless, they promulgated what may be the costliest environmental regulation to date. Notably, adverse effects remain difficult to demonstrate in occupationally exposed individuals even at blood concentrations 50-100 times higher than current background PFAS levels. Second, the Agency indicated that the epidemiology data showed that exposure to PFOA and PFOS caused kidney and potentially other cancers, yet the data were equivocal and do not support that assertion. Third, it was stated that specific non-cancer effects, such as heart disease, would be prevented under the promulgated rule; however, the studies that they relied upon do not show an increased incidence of heart disease even in highly exposed populations. Fourth, the Agency relied on animal data to support its views on the likely toxic effects in humans, despite ample toxicology data that animals, particularly rodents, are poor predictors of the human response to PFAS exposures. Fifth, the EPA predicted a reduction in healthcare expenditures that would offset much of the cost of complying with the MCL, but, they did not have adequate data to support this prediction. Sixth, the EPA suggested that these six PFAS act through a shared mechanism of action (i.e., PPARα pathway induction); however, data indicate that PPARα induction in humans may be 80% less than what is observed in rodents. Also, induction of the PPARα pathway is not a cause of systemic disease. Seventh, the Agency failed to disclose that achieving the new MCL would yield negligible reductions in blood PFAS levels even among highly exposed populations, given drinking water accounts for only 20% or less of total PFAS exposure. The survey that could answer that question, the EPA's fifth Unregulated Contaminant Monitoring Rule, was only 25% complete at the time the MCL was promulgated. Overall, our analysis concluded that while the EPA's intent to regulate these chemicals due to their environmental presence was necessary, the derivation of the MCLs and the alleged health effects was based on the application of the precautionary principle rather than robust scientific evidence.

PMID:40391660 | DOI:10.1080/10408444.2024.2446453

Crit Rev Toxicol. 2025 May 20:1-47. doi: 10.1080/10408444.2024.2415893. Online ahead of print.

ABSTRACT

In March 2023, the EPA proposed a 4.0 ppt maximum contaminant level (MCL) for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) (each) and a hazard index approach for four other PFAS. The EPA sought public feedback on the proposed MCL in early 2023 and received 1626 comment submissions via the PFAS docket website (Docket ID: EPA-HQ-OW-2022-0114). Final MCLs were promulgated on April 10, 2024. Our analysis of the PFAS docket identified 128 comments that had a reasonable degree of scientific merit, with 57 comments endorsing the regulations and 71 questioning the MCLs public health utility. Critics noted the lack of evidence for adverse health effects at low PFAS exposures, the rule's significant impact on the economy, and the EPA's selection of published papers which the Agency chose to support their views. Many well-substantiated comments highlighted that few, if any, adverse health effects were reported at doses as much as 100-1000 times above those associated with the proposed drinking water guidelines. We found that the comments which discussed the evidence linking PFAS exposures below 200 ppt in drinking water to adverse health effects were equivocal. Most of the well-documented science based comments indicated that the data did not justify setting a 4.0 ppt MCL. It was noted that the EPA MCL was quite different from drinking water standards in other countries (up to 8-140 fold lower). During the review, it became apparent that a 4.0 ppt MCL may have little effect on PFAS blood concentrations in most Americans since drinking water accounts for less than 20% of their total PFAS intake. Additionally, a significant portion of the American population consumes minimal amounts of tap water. Commenters noted that the financial burden for treatment and cleanup was much higher than what was reported in the justification for the final MCL which was submitted to the Office of Management and Budget (OMB) and eventually promulgated. It is possible that EPA underestimated the financial impact on the nation by up to 100 to 200-fold. Our analysis indicates that many, if not most, of the scientifically rigorous comments on the EPA's proposed MCL were not acknowledged or considered by the Agency. We conclude the article by offering sixteen recommendations for the EPA to consider if Congress or the courts choose to reopen the evaluation of these MCLs. These included convening an international expert panel, reevaluating the appropriateness of the LNT model for PFAS, ensuring adequate time for study quality assessment and cost-benefit analysis, considering an approach to implementing a series of MCLs, critically reevaluating scientific studies, adhering to EPA risk assessment guidelines, addressing SDWA compliance concerns, revisiting the Hazard Index approach, and ensuring thorough and transparent review of public comments.

PMID:40391661 | DOI:10.1080/10408444.2024.2415893

Environ Sci Technol. 2025 May 20. doi: 10.1021/acs.est.4c13813. Online ahead of print.

ABSTRACT

Amid growing concerns regarding the ecological risks posed by emerging contaminants, per- and polyfluoroalkyl substances (PFASs) present significant challenges for risk assessment due to their structural diversity and the paucity of experimental data on their bioaccumulation. This study investigated the bioconcentration factors (BCFs) of 18 emerging and legacy PFASs using zebrafish in a flow-through exposure system and constructed a robust BCF prediction model to address the data gaps associated with numerous novel PFASs. Experimental results indicated that perfluoro(3,5,7,9,11-pentaoxadodecanoic) acid (PFO5DoDA) and perfluoro-2,5-dimethyl-3,6-dioxanonanoic acid (C9 HFPO-TA) exhibited higher bioaccumulation potential than perfluorooctanoic acid (PFOA). A multimodal feature-fused directed message passing neural network (FF-DMPNN) model was constructed, integrating molecular graph representations, physicochemical descriptors, and bioassay data reflecting absorption, distribution, metabolism, and excretion characteristics. The FF-DMPNN model demonstrated superior predictive performance compared to conventional machine learning approaches by providing a more complete representation of molecular structures and physicochemical properties, achieving higher accuracy (R² = 0.742) and robustness in predicting BCF values for PFASs. Application of the model to a comprehensive PFAS database identified 2.45% of chemicals as bioaccumulative, highlighting the need for regulatory attention. Overall, this study provides critical insights into the bioconcentration risks associated with PFASs and offers a reliable framework for prioritizing regulatory actions for these emerging contaminants, addressing a pressing need for their effective environmental management.

PMID:40391855 | DOI:10.1021/acs.est.4c13813

Environ Sci Technol. 2025 May 20. doi: 10.1021/acs.est.4c13260. Online ahead of print.

ABSTRACT

Air pollution poses significant risks to human health and the environment, necessitating comprehensive monitoring and analysis to identify and mitigate the presence of harmful pollutants. This study focuses on Hamilton and Sarnia, Ontario, Canada, known for their industrial activities and associated air pollution challenges. Employing gas chromatography coupled with ion mobility spectrometry and high-resolution mass spectrometry (GC-IMS-MS) on samples collected by polyurethane foam passive samplers, we aimed to uncover the presence of halogenated airborne organic pollutants, including those not typically monitored in standard air quality assessments. Our research successfully identified 19 groups of halogenated pollutants in the air samples. These include a range of chlorinated and brominated anisoles, as well as a previously undocumented polyfluoroalkyl substance (PFAS) that was confirmed with a synthesized standard. Polychlorinated biphenyls (PCBs), chlorinated organophosphate esters (OPEs) and various agricultural contaminants were also tentatively identified based on mass spectral interpretation. The study revealed significant differences in the pollutant profiles between the two cities, reflecting their distinct industrial influences. The application of non-target screening techniques also highlighted the complex nature of air pollution and the necessity for broader monitoring strategies to protect public health and the environment.

PMID:40392056 | DOI:10.1021/acs.est.4c13260

Environ Sci Technol. 2025 May 20. doi: 10.1021/acs.est.5c03479. Online ahead of print.

ABSTRACT

The persistent leaching of per- and polyfluoroalkyl substances (PFAS) from landfills poses significant environmental risks, particularly to surrounding water systems. However, information regarding the occurrence and fate of PFAS in landfills across the country is limited. Here we investigated the distribution profiles and sources of 60 PFAS in landfill leachate across 31 provinces in mainland of China, showing the total levels of ∑PFAS from 3.05 × 10³ to 1.58 × 10⁵ ng/L. Structural equation modeling revealed that socioeconomic conditions directly influenced the residue levels of PFAS in landfill leachate. Furthermore, these conditions, in conjunction with climatic factors, influenced the chemical composition of landfill leachate, thereby indirectly affecting the distribution of PFAS. The estimated ∑PFAS emission flux from landfill leachate in China was 419 kg/year, with ultrashort-chain congeners as the predominant, omnipresent congeners, accounting for 37%. Our study first provided comprehensive evidence to demonstrate landfills were important sources of PFAS in China, which would help to understand the ecological risks of emerging PFAS, especially for ultrashort-chain PFAS, and eventually promoting the conduction effective environmental monitoring and pollution control strategies for PFAS.

PMID:40392082 | DOI:10.1021/acs.est.5c03479

Mar Pollut Bull. 2025 May 19;218:118110. doi: 10.1016/j.marpolbul.2025.118110. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are widespread in the environment, including the ocean. However, information on PFAS exposures in protected and endangered sea turtle species is scarce because sampling liver or blood is invasive and challenging. We assessed, for the first time, whether skin tissue, which is less invasive to collect, can be used to screen for PFAS in sea turtles. We measured concentrations of 20 PFAS in the skin and serum from deceased juvenile green turtles. Perfluorooctane sulfonic acid (PFOS) was the predominant PFAS and was detected in most of the skin (85 %) and serum (100 %). For individuals with paired skin and serum, PFOS concentrations were not significantly different, and thus suggest that skin samples have promising use for screening PFAS in sea turtles. This method may be adapted and optimized in the future to increase data coverage and improve our understanding of sea turtle exposures to PFAS.

PMID:40393330 | DOI:10.1016/j.marpolbul.2025.118110

Int J Hyg Environ Health. 2025 May 19:114528. doi: 10.1016/j.ijheh.2025.114528. Online ahead of print.

NO ABSTRACT

PMID:40393877 | DOI:10.1016/j.ijheh.2025.114528

J Environ Health. 2024 Jun;86(10):32-34.

NO ABSTRACT

PMID:40390762 | PMC:PMC12087759

Angew Chem Int Ed Engl. 2025 May 19:e202505383. doi: 10.1002/anie.202505383. Online ahead of print.

ABSTRACT

Redox flow batteries show promise for large-scale grid stabilisation. Of these, organic redox flow batteries (ORFBs) harbour the potential for sustainable and economic operation due to the materials deployed. Their long-term operation requires exquisite transport control of species across the cell, with movement of cations key for high current density, and anionic rejection needed for cycling stability. Nafion, although promising as a commercial separator, faces cost and sustainability limitations due to its fluorinated nature and per- and polyfluroralkyl substances (PFAS) generation. Here, we report the tailored combination of a hydrophilic mixed-matrix membrane, SPEEK-SX, with sulphonated polydichloroxylene (Sp-DCX) as the additive and sulphonated poly(ether ether ketone) (SPEEK) as the matrix. Compared to Nafion-212, the dense aromatic backbone of SPEEK efficiently rejected the crossover of electrolytes, with sulfonate groups housed within Sp-DCX micropores increasing Na⁺ mobility. SPEEK-SX2 exhibited 190 times higher Na⁺/ Fe(CN)₆ ^4- selectivity and 6 times higher Na⁺/ 2,6-DHAQ^2- selectivity compared to Nafion-212. This enabled stable operation for 600 cycles at a high current density of 160 mA cm^-2 with only 0.00935% per cycle capacity decay. In contrast, the SPEEK membrane exhibited 0.07% per cycle decay, whereas Nafion-212 failed to run at this high current density.

PMID:40384084 | DOI:10.1002/anie.202505383

Environ Res. 2025 May 16:121846. doi: 10.1016/j.envres.2025.121846. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are synthetic environmental contaminants with widespread industrial and consumer applications, characterized by strong chemical stability and environmental persistence. Recent studies have highlighted placental permeability to PFAS, though evidence of direct histopathological impairment remains limited. This study aimed to investigate potential associations between PFAS exposure and histopathological abnormalities in placental samples. A total of 23 at-term pregnant women were recruited from two hospitals in Italy as part of a multicenter study. Placental samples, divided into maternal (decidua) and fetal (villi) compartments, were analyzed for PFAS concentration and histopathological alterations. PFAS were detected in 95.7% of samples. The most frequently detected PFAS were PFOS (88%), followed by PFHxS (83%), PFOA (83%), PFBS (54%) and PFHxA (54%). Preliminary findings suggest variable PFAS concentrations among subjects, with histopathological examination revealing placental alterations of potential clinical relevance. The observed histopathological alterations, particularly in cases of malperfusion and angiogenesis changes, suggest that PFAS may contribute to placental dysfunction, potentially affecting pregnancy outcomes. In particular, it could be hypothesized that PFHxA could exert an adverse influence on placental angiogenesis, due to pre-placental hypoxia stimulating the angiogenesis and resulting in increased ramification and number of branches. While direct causative links remain to be fully elucidated, these results underscore the need for further investigations into PFAS-related placental effects and their implications for fetal development.

PMID:40383424 | DOI:10.1016/j.envres.2025.121846

J Chem Phys. 2025 May 21;162(19):194902. doi: 10.1063/5.0267483.

ABSTRACT

Novel molecules containing a silane anchor, a hydrocarbon segment, and a polyethylene glycol (PEG) head have been developed to functionalize membranes for capture of per and poly-fluoroalkyl species (PFAS). The membranes have been experimentally tested against PFAS-contaminated water. Based on previous experimental testing and molecular modeling, the length of the hydrophobic PEG segment was identified as a potential feature to improve filter performance, particularly against low molecular-weight, short-chain PFAS. In our previous work, silane molecules featured an eight-carbon hydrocarbon segment and a segment with four consecutive PEG monomers. In this work, versions of the silane molecules with both shorter and longer PEG segments were synthesized and tested. We report results from tests measuring the dynamic filtration ability of aluminum-oxide hydroxide membranes functionalized with amphiphilic molecules against PFAS at part-per trillion and part-per billion concentration levels. Filters utilizing silanes with shorter PEG segments outperformed those with longer PEG segments, particularly against short-chain PFAS. Molecular dynamics simulations using metadynamics sampling methods were employed to construct free-energy interaction profiles, and interaction energies between several different contaminant species and a silane brush layer. Decomposition of the interaction free energy into the molecular interaction contributions to the potential energy (enthalpy) highlights the influence of PFAS length, PEG length, and brush geometry on the overall PFAS-brush interaction. Experimental measurements indicate that membrane performance depends on the length of the PEG segment in the silane brush. Combined experimental and simulation results indicate that both the intermolecular interaction strength and the density of the surface coating depend on the length of the PEG segment. The experiment and simulation results also show that both molecular architecture and membrane processing impact the overall filter performance.

PMID:40377198 | DOI:10.1063/5.0267483

Environ Sci Technol. 2025 May 16. doi: 10.1021/acs.est.5c02035. Online ahead of print.

ABSTRACT

Due to the lack of transparency in the production and applications of emerging per- and polyfluoroalkyl substances (PFAS), it is a huge challenge to grasp the real PFAS pollution profile in a specific region or industry by target analysis. This study collected extensive samples across China, including municipal wastewater from 9 major cities and wastewater from various manufacturing stages at 3 large semiconductor factories. Suspect and nontarget screening were conducted along with target analysis, and 82 PFAS in 25 classes were identified. Notably, this is the first study to investigate PFAS contamination in semiconductor wastewater on the Chinese mainland. Moreover, 13 classes of PFAS were reported for the first time worldwide in semiconductor wastewater, including multiple hydrosubstituted perfluoroalkyl carboxylic acid (mH-PFCA), ether-inserted PFCA (OPFCA), and perfluoroalkyl alcohol (PA) derivatives. The highest total concentrations of target, suspect, and nontarget PFAS in semiconductor wastewater (12 μg/L) were substantially higher than those measured in all municipal wastewater (25-950 ng/L). The composition of PFAS varied regionally in semiconductor wastewater. Total oxidizable precursor assay revealed the presence of unknown precursors (0.043-0.83 nmol/L), which cannot be directly monitored but may pose a greater PFAS contamination risk in semiconductor water treatment and discharge processes.

PMID:40378070 | DOI:10.1021/acs.est.5c02035

Water Res. 2025 May 8;283:123794. doi: 10.1016/j.watres.2025.123794. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) pose a significant challenge for water treatment facilities facing strict regulatory standards. Granular activated carbon (GAC) adsorption is effective for PFAS removal, but media exhaustion and replacement can be costly, highlighting the need for innovative GAC regeneration methods. While thermal reactivation of GAC can eliminate adsorbed PFAS, it requires high temperatures and is mainly feasible for large-scale media users. This study investigates spent GAC regeneration by hydrothermal alkaline treatment (HALT), which applies subcritical water (e.g., 350 °C, 16.5 MPa) amended with strong base (e.g., NaOH) to destroy PFAS. Previous research indicates that HALT successfully degraded and defluorinated PFAS while maintaining GAC surface area and equilibrium adsorption capacity. This study presents data from rapid small-scale column tests (RSSCTs) demonstrating effective removal of long-chain PFAS by a HALT-treated spent GAC sample collected from a long-term PFAS treatment field pilot study (BV₅₀ > 50,000 for PFOS, PFHxS, and PFNA). HALT-treated virgin GAC and untreated virgin GAC evaluated using RSSCTs exhibited similar PFAS breakthrough behavior, with comparable overall PFAS removal to the HALT-treated spent GAC. Physisorption measurements revealed that HALT recovers GAC pore surface area lost during field-use. Surface chemical characterization techniques indicated mostly similar surface composition and functional groups in virgin and HALT-treated GAC, with limited change in the carbon structure following HALT and differences between virgin and field-spent samples. Analyses of reactor liquid products, media mass loss, and NaOH neutralization by GAC also provided evidence for removal of adsorbed non-target organic matter and possible GAC surface renewal by carbon gasification reactions occurring in parallel with PFAS destruction, analogous to surface carbon burn-off that occurs during high-temperature thermal reactivation. Retention of adsorbed metal ions that accumulated on the spent GAC during field testing may be responsible for enhanced adsorption behavior observed for some PFAS following HALT regeneration. Results indicate that HALT can enable reuse of spent GAC, potentially alleviating the high demand for virgin media in PFAS treatment processes.

PMID:40378469 | DOI:10.1016/j.watres.2025.123794

Spectrochim Acta A Mol Biomol Spectrosc. 2025 May 8;340:126356. doi: 10.1016/j.saa.2025.126356. Online ahead of print.

ABSTRACT

The high dissociation energy of C-F bonds makes the natural degradation and decomposition of PFAS (per- and poly-fluoroalkyl substances) nearly impossible, leaving the PFAS wastes widely dispersed and permanently persisting in the natural environment. Consequently, detection and recognition techniques, as well as treatment technology, are highly desired for perfluorooctane sulfonate (PFOS) pollutants. In this work, we designed a core-shell magnetic-porous composite structure (denoted as Fe₃O₄@MCM-41/EY) for the sensing, adsorption, and removal of PFOS, using EY:CTAB (0.5 μM:80 μM, EY = Eosin Y, CTAB = cetyltrimethylammonium bromide) as the sensing probe, Fe₃O₄ nanoparticles as the core, and porous silica MCM-41 as the shell. The composite structure of Fe₃O₄@MCM-41/EY was confirmed by means of SEM (scanning electron microscope), magnetism, XRD (X-ray diffraction), N₂ adsorption/desorption, and TGA (thermal gravimetric analysis). A probe loading level of 28.5 % was determined. The probe showed an emission turn-on effect toward PFOS owing to the viscosity variation of the micelles caused by PFOS. A linear fitting equation was obtained as I/I₀ = 1.081 + 0.144 × 10⁶[PFOS], R² = 0.990, with good sensing selectivity and LOD (limit of detection) of 0.27 μM. In addition, Fe₃O₄@MCM-41/EY removed PFOS efficiently with an adsorption capacity of 0.126 mg/g. The novelty of this work was the simultaneous sensing, adsorption, and removal of PFOS using a core-shell magnetic-porous composite structure.

PMID:40378487 | DOI:10.1016/j.saa.2025.126356

Environ Res. 2025 May 14:121865. doi: 10.1016/j.envres.2025.121865. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFASs) are extensively utilized as oilfield production chemicals and aqueous film-forming foams (AFFFs) in oilfields. A comprehensive investigation was undertaken to analyze twenty per-and polyfluoroalkyl substances (PFASs), including three emerging PFASs in drill cuttings, slurry and produced water from offshore oilfields in three main sea areas of China. The investigation results were further compared with those in their receiving water. The concentration ranges of ΣPFASs in drill cuttings, slurry as well as produced water were 1049-3473 ng/g and 81.9 ng/L-2090 ng/L, respectively. In comparison, the concentrations range of PFASs in receiving water was 46.2-99.7 ng/L. Both sodium p-perfluorous nonenoxybenzenesulfonate (OBS) and hexafluoropropylene oxide dimer acid (HFPO-DA) were identified as the predominant PFASs detected at elevated concentrations in drilling cuttings, slurry, and produced water, demonstrating their extensive utilization in such environments. HFPO-DA and OBS concentrations in produced water exceeded those in receiving water by 1-2 orders of magnitude. Principal component analysis (PCA) analyses revealed that the compositions of PFASs in the receiving water samples exhibited significant similarity to those in drill cuttings, slurry and produced water from oilfields. It was indicated that discharges from oilfields were the primary contributors of PFASs in their receiving water. In 60-96% of samples from produced water in the Bohai Sea and South China Sea oilfields, as well as receiving water adjacent to the Bohai Sea oilfields, the risk quotient (RQ) of HFPO-DA ranged 0.1-1, indicating moderate ecological risks to aquatic organisms. In contrast, legacy PFASs generally showed lower risk levels.

PMID:40378999 | DOI:10.1016/j.envres.2025.121865

ACS ES T Water. 2025 Apr 7;5(5):2322-2332. doi: 10.1021/acsestwater.4c01222. eCollection 2025 May 9.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are difficult to treat by using conventional drinking water treatment technologies. Herein, we upgrade a commercially available powder activated carbon (PAC) via an acid wash and pyrolysis to amplify hydrophobicity and enhance PFAS adsorption. Minimal differences in overall surface area, micropore volume and area, and external surface area were observed between acid-washed and pyrolyzed PACs. X-ray photoelectron spectroscopy, contact angle measurements, and scanning electron microscopy evidenced ∼5% reduced oxygen content and noticeable hydrophobicity increases for the pyrolyzed PAC, without altering morphology. Adsorption isotherms of perfluorooctanoic acid (PFOA) showed no major increases to adsorption capacity, but more rapid adsorption kinetics of PFOA and perfluorobutanesulfonic acid (PFBS) to the pyrolyzed PAC, in both low and high PFAS concentration tests, were revealed in both reagent water and synthetic natural organic matter, with overall greater removal values (e.g., ∼90% removal vs 60%, in water after 1 h at 2 mg/L PFOA). PFOA and PFBS adsorption behavior adhered to pseudo-second-order kinetics (R ² = 0.843-0.992). Density functional theory calculations quantitatively evaluated adsorption energies of PFOA and PFBS onto a graphene skeleton containing different organic functional groups, finding supportive outcomes. This work greater informs the importance of hydrophobicity for PFAS adsorption onto PAC.

PMID:40371378 | PMC:PMC12070405 | DOI:10.1021/acsestwater.4c01222

Mar Pollut Bull. 2025 May 13;217:118140. doi: 10.1016/j.marpolbul.2025.118140. Online ahead of print.

ABSTRACT

This study investigated the distribution and composition of 28 per- and polyfluoroalkyl substances (PFASs) in surface and core sediments from the regional seas of South Korea. Surface sediments were collected from the Yellow Sea (YS, n = 10), East China Sea (ECS, n = 6), South Sea (SS, n = 5), and East Sea (ES, n = 12), and core sediments were obtained from the ES (n = 3, 0-30 cm). Sediment samples were extracted with methanol by shaking, followed by purification using solid-phase extraction cartridges. The purified extracts were then analyzed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to quantify 11 perfluoroalkyl carboxylic acids, 9 perfluoroalkyl sulfonic acids, 5 precursors, and 3 emerging PFASs. The highest PFAS concentrations in surface sediments were observed in the YS (300 ng g^-1 organic carbon (OC)), followed by the ES (150 ng g^-1 OC), ECS (120 ng g^-1 OC), and SS (14 ng g^-1 OC). Core sediment analysis revealed the accumulation of PFASs within the top 10 cm depth at the dumpsite, along with elevated OC contents (2.7-4.4 %) and lighter carbon stable isotope ratios (δ¹³C, -23 to -22 ‰) indicating the influence of dumped wastes. Principal component analysis classified the sites into three groups based on chemical composition, reflecting regional differences in PFASs usage, transport, and deposition. These findings provide critical insights into the distribution and environmental behavior of PFASs in marine sediments and contribute to developing future regulatory frameworks and pollution management strategies.

PMID:40373573 | DOI:10.1016/j.marpolbul.2025.118140

Environ Pollut. 2025 May 13;377:126443. doi: 10.1016/j.envpol.2025.126443. Online ahead of print.

ABSTRACT

In mammals, exposure to PFAS is usually assessed by measuring burdens in internal organs (i.e., liver and brain) or plasma, while less emphasis is devoted to non-invasive and non-destructive methods. We assess the suitability of hair as a non-invasive matrix for monitoring the exposure of mammals to 33 PFAS, including perfluoroalkyl carboxylic acids (PFCAs), perfluoroalkane sulfonic acids (PFSAs), perfluoroalkylether carboxylic acids (PFECAs), perfluoroalkylether sulfonic acids (PFESAs), perfluoroalkane sulfonyl fluoride-based substances (PASFs), and fluorotelomers (FTs). The Red fox is chosen as the target species due to its apical position in the terrestrial food web of the study area, the Cavallino-Treporti peninsula in North-East Italy. All analysed samples (n = 24) are positive for PFAS, with eight compounds quantified in all samples, including PFHxA, PFOA, PFDA, PFUnDA, PFDoDA, PFTriDA, PFTeDA, and PFOS. The highest mean concentration in hair samples is measured for PFOS (1.40 ± 0.48 ng g^-1 dw) followed by PFDoDA (0.31 ± 0.05 ng g^-1 dw), and PFOA (0.31 ± 0.19 ng g^-1 dw), while the mean ∑₃₃PFAS was 3.41 ± 0.93 ng g^-1 dw. The dominance of PFOS and long-chain PFAS in the PFAS profile and the occurrence of compounds with even-numbered carbon chains at higher concentrations than the odd-numbered compounds with a one-carbon longer chain (i.e., PFOA > PFNA, PFDA > PFUnDA, PFDoDA > PFTriDA) suggest the trophic transfer along the terrestrial food web as the primary exposure pathway in the study area. The data suggest hair analysis as a reliable, non-invasive method for assessing the possible exposure of mammals to PFAS and suggested that the Red fox can be used as a sentinel of the environment, embracing the One Health perspective.

PMID:40373857 | DOI:10.1016/j.envpol.2025.126443

Food Risk Assess Eur. 2025 Apr;3(2):0057E. doi: 10.2903/fr.efsa.2025.FR-0057. Epub 2025 May 12.

ABSTRACT

Per- and polyfluorinated alkyl substances (PFAS) comprise a wide range of industrial chemicals that are currently being evaluated worldwide for their toxic and bioaccumulative properties. Some of these chemicals are already subject to restrictions. The Austrian Drinking Water Regulation (Trinkwasserverordnung, BGBl. II Nr. 304/2001, consolidated version of 16.05.2024) sets a limit of 0.1 μg/L for the sum of 20 PFAS in drinking water from 12 January 2026 as prescribed by Directive (EU) 2020/2184 [1]. However, a large number of PFAS are not covered by this Directive. For some of these compounds, provisional drinking water tolerance values for both adults and infants have been derived in this work. Toxicological assessments and drinking water guideline values derived by other authorities as well as scientific studies were used for this purpose. These provisional tolerance values were compared with the occurrence data of Austrian drinking water and groundwater, as were the health-based guidance values (HBGVs) with the estimated exposure. The tolerance values for adults were not exceeded; however, some measurements for GenX were above the derived provisional tolerance values for infants. The estimated exposures based on the concentrations of PFAS in ground or drinking water did not exceed the HBGVs, yet for infants, the highest levels reached 45 % of the HBGV in the case of GenX. While no immediate health risks are to be anticipated, it is important to ensure that concentrations of PFAS do not increase further.

PMID:40370710 | PMC:PMC12077312 | DOI:10.2903/fr.efsa.2025.FR-0057

Foods. 2025 Apr 23;14(9):1461. doi: 10.3390/foods14091461.

ABSTRACT

Seafood plays a vital role in human diets worldwide, serving as an important source of high-quality protein, omega-3 fatty acids, and essential vitamins and minerals that promote health and prevent various chronic conditions. The health benefits of seafood consumption are well documented, including a reduced risk of cardiovascular diseases, improved cognitive function, and anti-inflammatory effects. However, the safety of seafood is compromised by multiple hazards that can pose significant health risks. Pathogenic microorganisms, including bacteria, viruses, and parasites, in addition to microbial metabolites, are prominent causes of the foodborne diseases linked to seafood consumption, necessitating reliable detection and monitoring systems. Molecular biology and digital techniques have emerged as essential tools for the rapid and accurate identification of these foodborne pathogens, enhancing seafood safety protocols. Additionally, the presence of chemical contaminants such as heavy metals (e.g., mercury and lead), microplastics, and per- and polyfluoroalkyl substances (PFASs) in seafood is of increasing concern due to their potential to accumulate in the food chain and adversely affect human health. The biogenic amines formed during the microbial degradation of the proteins and allergens present in certain seafood species also contribute to food safety challenges. This review aims to address the nutritional value and health-promoting effects of seafood while exploring the multifaceted risks associated with microbial contamination, chemical pollutants, and naturally occurring substances. Emphasis is placed on enhanced surveillance, seafood traceability, sustainable aquaculture practices, and regulatory harmonization as effective strategies for controlling the risks associated with seafood consumption and thereby contributing to a safer seafood supply chain.

PMID:40361542 | PMC:PMC12071223 | DOI:10.3390/foods14091461

Molecules. 2025 Apr 29;30(9):1989. doi: 10.3390/molecules30091989.

ABSTRACT

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are widely utilized in food contact materials (FCMs) due to their water- and oil-repellent properties, yet their potential migration into food raises significant health concerns. This study employs high-resolution mass spectrometry (HRMS) to quantify the migration of 40 PFAS from microwave popcorn bags and assess the associated health risks. HRMS offers high mass accuracy and resolution, enabling precise detection of a broad spectrum of PFASs, including those with low migration levels. Migration experiments were conducted using 10% ethanol and 50% ethanol as food simulants at 70 °C for 2 h. The results indicate that when risk assessment is based solely on the European Food Safety Authority's (EFSA) tolerable weekly intake (TWI) for four PFAS, hazard ratio (HR) values range from 0.01 to 0.8, suggesting minimal risk. However, when all PFAS are converted into perfluorooctanoic acid equivalents (PEQs) and compared against the U.S. Environmental Protection Agency's (EPA's) reference dose (RfD), HR values range from 0.3 to 142.3, indicating a significantly elevated health risk. These findings emphasize the necessity of comprehensive risk assessments incorporating the cumulative effects of all PFAS to better understand potential human exposure and inform regulatory policies.

PMID:40363795 | PMC:PMC12073814 | DOI:10.3390/molecules30091989

Environ Sci Technol. 2025 May 14. doi: 10.1021/acs.est.4c11872. Online ahead of print.

ABSTRACT

People are exposed to per- and polyfluoroalkyl substances (PFAS) through multiple sources, with diet historically considered a major source in general populations. This study characterized legacy PFAS in serum from 700 California adults and examined contributions from diet and drinking water. We applied robust regression to estimate associations between nontransformed serum PFAS concentrations, self-reported food consumption, and drinking water PFAS concentrations measured under the USEPA's third Unregulated Contaminant Monitoring Rule (2013-2015). Detectable drinking water concentrations were associated with increased serum perfluorooctanoic acid (PFOA) (0.26 ng/mL; 95% CI: 0.077, 0.43), perfluorohexanesulfonic acid (PFHxS) (0.64 ng/mL; 95% CI: 0.058, 1.23), and perfluorooctanesulfonic acid (PFOS) (0.39 ng/mL; 95% CI: -0.76, 0.86). Seafood consumption was associated with increased perfluorononanoic acid (PFNA) (0.013 ng/mL; 95% CI: 0.0058, 0.021), perfluorodecanoic acid (PFDeA) (0.0059 ng/mL; 95% CI: 0.0026, 0.0092), and perfluoroundecanoic acid (PFUnDA) (0.010 ng/mL; 95% CI: 0.0054, 0.015), while eggs were associated with increased PFDeA (0.0035 ng/mL; 95% CI: 0.00010, 0.0069) and PFNA (0.0073 ng/mL; 95% CI: 0.00017, 0.014). Findings could indicate that dietary contributions may be less than those in earlier studies conducted in other populations, possibly due to shifts in PFAS production over the past 20 years, and that drinking water remains an important source of exposure to PFOA and PFHxS in this population.

PMID:40365998 | DOI:10.1021/acs.est.4c11872

PDA J Pharm Sci Technol. 2025 May 14;79(2):240-241. doi: 10.5731/pdajpst.2025.25203.

ABSTRACT

In February 2023 a restriction proposal to the European Chemicals Agency (ECHA) was submitted by five member countries of the European Union proposing a substantial restriction under the Registration, Evaluation, Authorization and Restriction of Chemical substances (REACH) regulation Annex XV for the use of all PFAS variants, thereby potentialy listing all PFASs as Substances of Very High Concern (SVHC).

PMID:40368594 | DOI:10.5731/pdajpst.2025.25203

PDA J Pharm Sci Technol. 2025 May 14;79(2):240-241. doi: 10.5731/pdajpst.2025.25203.

ABSTRACT

In February 2023 a restriction proposal to the European Chemicals Agency (ECHA) was submitted by five member countries of the European Union proposing a substantial restriction under the Registration, Evaluation, Authorization and Restriction of Chemical substances (REACH) regulation Annex XV for the use of all PFAS variants, thereby potentialy listing all PFASs as Substances of Very High Concern (SVHC).

PMID:40368594 | DOI:10.5731/pdajpst.2025.25203

Food Res Int. 2025 Jun;211:116463. doi: 10.1016/j.foodres.2025.116463. Epub 2025 Apr 19.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) contamination in aquatic and terrestrial organisms poses significant environmental and health risks. This study quantified 15 PFAS compounds across various tissues (liver, kidney, gill, muscle, skin, lung, blood, breast, feather) from fish (Clarias gariepinus, Oreochromis niloticus, Lates niloticus, Tilapia zilli), livestock (camel, cow, sheep, ram, goat), and birds (pigeon, chicken, turkey). Among the fishes, C. gariepinus exhibited the highest PFAS accumulation, with PFOA (46.5 ng/g) and PFTrDA (50.1 ng/g) dominant in liver and kidney, while O. niloticus showed elevated PFTrDA (56.87 ng/g) and PFUnDA (29.43 ng/g). In livestock, camel liver contained high PFNA (9.22 ng/g), and cow liver had the highest PFOS (8.1 ng/g). Among the birds, pigeon liver showed the highest PFNA (7.83 ng/g). To analyze PFAS distribution patterns, dimensionality reduction and clustering techniques were employed. Principal Component Analysis (PCA) captured 68.28 % of total variance, revealing two distinct clusters whereby fish species are strongly related with higher PFAS concentration, while poultry showed unique PFAS profiles when compared to other types of meat. Clustering of PFOS, PFOA, and other PFAS compounds near the center explained their influence across the general meat types particularly the fish species, while t-Distributed Stochastic Neighbor Embedding (t-SNE) confirmed clear separations in high-dimensional space. Clustering analyses, including K-means, hierarchical clustering, DBSCAN, and Gaussian Mixture Models (GMM), identified well-defined patterns, with DBSCAN and GMM detecting overlapping categories and outliers. Feature importance analysis using a Random Forest model highlighted total PFAS as the most significant predictor, with PFHxA and PFDODA also contributing strongly, while organ type and species played a lesser role. These findings demonstrate the effectiveness of unsupervised learning techniques in characterizing PFAS bioaccumulation patterns across species and tissues, providing valuable information for ecological and toxicological risk assessments.

PMID:40356129 | DOI:10.1016/j.foodres.2025.116463

Nanomaterials (Basel). 2025 Apr 25;15(9):655. doi: 10.3390/nano15090655.

ABSTRACT

GenX, the trade name of hexafluoropropylene oxide dimer acid (HFPO-DA) and its ammonium salt, is a short-chain PFAS that has emerged as a substitute for the legacy PFAS perfluorooctanoic acid (PFOA). However, GenX has turned out to be more toxic than people originally thought. In order to monitor and regulate water quality according to recently issued drinking water standards for GenX, rapid and ultrasensitive detection of GenX is urgently needed. For the first time, this study reports ultrasensitive (as low as 1 part per billion (ppb)) and fast detection (in minutes) of GenX in water via surface-enhanced Raman spectroscopy (SERS) using a hierarchical nanofibrous SERS substrate, which was prepared by assembling ~60 nm Ag nanoparticles on electrospun nylon-6 nanofibers through a "hot start" method. The findings in this research highlight the potential of the engineered hierarchical nanofibrous SERS substrate for enhanced detection of short-chain PFASs in water, contributing to the improvement of environmental monitoring and management strategies for PFASs.

PMID:40358272 | PMC:PMC12073261 | DOI:10.3390/nano15090655

Int J Hyg Environ Health. 2025 May 12;267:114592. doi: 10.1016/j.ijheh.2025.114592. Online ahead of print.

ABSTRACT

BACKGROUND: Legacy per- and polyfluoroalkyl substances (PFAS) can promote dyslipidemia; however, evidence is lacking for alternative and precursor PFAS. We investigated associations between serum concentrations of 31 PFAS and concurrently measured lipids and liver function biomarkers.

METHODS: PFAS, lipids, and liver function biomarkers were analyzed in serum samples provided by 282 adult females participating in a 2018-2021 follow-up study of a Canadian pregnancy cohort. We examined percent differences in outcomes continuously for 17 PFAS with >50% detection and as detected vs. not detected for 14 PFAS with 10-50% detection. We also examined associations with the sum of 7 PFAS recommended by the National Academies of Sciences, Engineering, and Medicine guidance report on PFAS testing and 17 PFAS. We used weighted quantile sum (WQS) and quantile g-computation models to estimate joint associations.

RESULTS: Each two-fold increase in concentrations of PFHxS, PFOS, PFNA, PFDA, PFHpS, and Σ7PFAS were associated with up to 7% higher total and LDL cholesterol and the TC:HDL ratio. Individuals with detectable concentrations of N-EtFOSA, N-MeFOSA, PFBS, and 9Cl-PF3ONS had up to 17% higher total and LDL cholesterol and TC:HDL. Each one-quartile increase in the mixture of 7 PFAS was associated with up to 10% higher total and LDL cholesterol. Adding additional PFAS to the mixture (17 PFAS) made estimates less precise in WQS models and attenuated associations to the null in quantile g-computation models.

CONCLUSION: Alternative and precursor PFAS, including replacements for legacy PFAS, are associated with higher cholesterol levels; prospective studies are required to confirm these findings.

PMID:40359778 | DOI:10.1016/j.ijheh.2025.114592

Water Res. 2025 Apr 30;282:123758. doi: 10.1016/j.watres.2025.123758. Online ahead of print.

ABSTRACT

We explored an underexplored area in water treatment by examining the removal of per- and polyfluoroalkyl substances (PFAS) from reverse osmosis/nanofiltration (RO/NF) brine. We first compared multiple RO/NF membranes, revealing that DK and NF270 showed sub-optimal removal (<90 %) of C4-C8 PFAS, SW30 had low flux (<15 L/m²/h at 8 bar), and NFX exhibited significant adsorption of perfluorosulfonic acids (e.g., 8 µmol/m²). To address the PFAS-enriched brine generated from membrane treatment, we further evaluated activated carbon (GAC) and anion-exchange (AIX) resin, both of which efficiently removed moderate- and long-chain PFAS from brine. Although AIX outperformed GAC, the ion exchange contribution was small for short-chain PFAS like perfluorobutanoic acid (PFBA, C4) but increased with chain length, driven by the hydrophobic effect facilitating the migration to near-surface regions of resins. Equilibrium batch experiments and thermodynamic modeling revealed a disproportionate salinity impact on PFAS adsorption by GAC, with short-chain PFAS (e.g., PFBA) experiencing more pronounced adsorption reduction than longer-chained homologs as NaCl concentrations increased. This reduction was driven by a significant change in a free energy component unrelated to the hydrophobic or electrostatic interactions, likely due to the competitive adsorption of Cl^- ions and short-chain PFAS anions or the formation of hydration shells around Na⁺ and Cl^- ions, obstructing the pathways for weakly hydrophobic PFAS (e.g., PFBA) within the GAC pore network. The salting-out effect was found to be unimportant. This study provides new insights into salinity-dependent sorptive removal of PFAS from high-ionic-strength water such as RO/NF brine.

PMID:40359825 | DOI:10.1016/j.watres.2025.123758

J Sep Sci. 2025 May;48(5):e70155. doi: 10.1002/jssc.70155.

ABSTRACT

The liquid chromatography / mass spectrometry (LC/MS) quantification of per- and polyfluoroalkyl substances (PFAS) in complex matrices presents challenges. Despite advanced sample preparation techniques to isolate analytes, residual matrix components can still interfere with MS detection. Additionally, extracts often contain high levels of organic solvents limiting the volume that can be injected when using reversed-phase HPLC. Yet, increasing the injection volume could be a simple path to lower detection limits. Feeding PFAS samples, dissolved in pure acetonitrile, at controlled speed into the stream of mobile phase resulted in an analyte focusing effect on the column. By using this approach, the injection volume could be increased 10 times compared to the conventional injection mode, as did the detection sensitivity. Feed injection was coupled to two-dimensional liquid chromatography (2D-LC) in a configuration in which the same triple quadrupole MS could be used for detection in both separation dimensions. The improved separation markedly reduced ion suppression effects and allowed to distinguish the critical PFAS compound perfluorobutanoic acid (PFBA) from isomeric matrix components within tomato extracts interfering with its quantification when only LC/MS was used. This 2D-LC/MS approach therefore fulfilled recommendations that PFBA should be analyzed using a secondary LC approach, without adding a marked amount of time to the analysis.

PMID:40361260 | DOI:10.1002/jssc.70155

Anal Bioanal Chem. 2025 May 12. doi: 10.1007/s00216-025-05902-3. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) make up a large and complex class of manmade chemicals. They have been widely used in numerous industrial branches and are incorporated into many consumer products. Today, there is a consensus on the fact that PFAS are present in all environmental compartments and that populations all over the world are subjected to them via internal exposure. It has been estimated that thousands of individual PFAS have been manufactured and marketed since the 1950s, to which impurities present in commercial products and intermediate environmental transformation products should be added. Since it is unrealistic to be able to individually identify, detect and quantify all the PFAS present in a sample, several analytical approaches have been developed to assess the presence of "hidden/unseen" PFAS. One of these, known as the total oxidisable precursor (TOP) assay, was first described in 2012. Basically, it converts some PFAS, hereafter referred to as precursors, into stable terminal products readily measurable by routine target methods. This review is based on more than 100 studies in which the original TOP assay was simply applied or optimised. The review found that the TOP assay was selective, sensitive, applicable to many matrices, useful within a forensic context, inexpensive, and easy to implement and has been assessed in the literature on a wide range of precursors. However, this method comprises many subtleties and has some flaws that operators should be made aware of so that they may be addressed as far as possible. Finally, this review tries to lay the foundations for better practices and quality assurance/quality control measures, in order to improve accuracy and reliability of TOP assay results.

PMID:40353877 | DOI:10.1007/s00216-025-05902-3

Environ Res. 2025 May 10;279(Pt 1):121827. doi: 10.1016/j.envres.2025.121827. Online ahead of print.

ABSTRACT

Per-and polyfluoroalkyl substances (PFAS) are a pervasive family of synthetic compounds with a wide range of reported health effects. Epigenetic clocks, DNA methylation-based predictors of chronological and biological age, are promising biomarkers for characterizing biological aging in humans. The potential impact of PFAS exposure on epigenetic aging in the general US population remains unclear. In the 1999-2000 National Health and Nutrition Examination Survey (NHANES) cycle (N = 262), eleven PFASs were measured in serum and DNA methylation was measured in blood with the EPICv1 array. Seven epigenetic clocks and their respective epigenetic age acceleration (EAA) measures were calculated. Survey-design weighted generalized linear regression models were used to test adjusted associations between individual log₂-transformed PFAS concentrations and EAA stratified by sex. Among male participants, doubling of PFNA concentrations was associated with greater EAA across several clocks including the Horvath clock (beta = 1.48, 95 % CI: 0.35, 2.61), Skin&Blood clock (beta = 1.27, 95 % CI: 0.21, 2.32), and PhenoAge (beta = 1.43, 95 % CI: 0.41, 2.44), and doubling of PFOS exposure was associated with greater Skin&Blood EAA (beta = 1.14, 95 % CI: 0.04, 2.24). When considering cell-adjusted EAA measures, each of these associations among male participants remained significant, and PFOSA was associated with decreased PhenoAge EAA (beta = -0.84, 95 % CI: -1.49, -0.18) and GrimAge2 EAA (beta = -0.81, 95 % CI: -1.51, -0.11) among female participants. In summary, we found evidence of sex-specific associations between PFAS exposure and epigenetic aging in a sample of older adults representative of the general US population.

PMID:40355061 | DOI:10.1016/j.envres.2025.121827

Environ Pollut. 2025 May 10;376:126420. doi: 10.1016/j.envpol.2025.126420. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are a large family of synthetic fluorinated chemicals. Studies using multiple analytical approaches to evaluate PFAS-contaminated soils are still limited, potentially leading to an underestimation of PFAS pollution. This study introduced a stepwise analytical workflow for a comprehensive assessment of organofluorine, integrating total fluorine (TF) determination, extractable organofluorine (EOF) analysis, PFAS target analysis, and PFAS precursor oxidative conversion assay. The workflow was applied to ten field soil samples collected from aqueous film-forming foam (AFFF)-contaminated sites. The sum target PFAS concentration (∑PFAS) ranged from 51.8 to 23200 ng/g dry weight. Perfluorooctanesulfonic acid was the predominant PFAS, accounting for 13 %-82 % (mean value: 53 %) of the ∑PFAS. Target PFAS accounted for 1 %-80 % of the EOF in the soil samples, and the integration of oxidative conversion revealed additional EOF contributions ranging from 0 % to 31 %. However, a considerable proportion (20 %-94 %) of unknown organofluorine still persists after combining targeted PFAS analysis and oxidative conversion, likely due to non-oxidizable PFAS, incomplete conversion of unknown PFAS precursors, and persistence of ultra-short chain PFAS post oxidative conversion. In addition, a significant positive correlation was observed between oxidative conversion and EOF results, but not with PFAS target analysis, suggesting that oxidative conversion may better represent the organofluorine burden in AFFF-impacted soils. Our findings indicate that TF analysis is unsuitable for tracing PFAS contamination in soils. Instead, combining oxidative conversion with routine PFAS target analysis is recommended to comprehensively assess PFAS contamination in soils.

PMID:40355065 | DOI:10.1016/j.envpol.2025.126420

Environ Pollut. 2025 May 10:126401. doi: 10.1016/j.envpol.2025.126401. Online ahead of print.

ABSTRACT

This research addresses a knowledge gap in the detectability, concentrations, and types of per and polyfluoroalkyl substances (PFAS) present in shallow soils in England, UK. While the water environment has been, and continues to be, the subject of significant testing and research for these chemicals, soils are still poorly understood. Estimates of anthropogenic background concentrations of PFAS helps with the assessment of potential contamination scenarios, setting benchmark levels and risk evaluation. This research comprised an assessment of the suitability of using archive soil samples to support contemporary samples to give a preliminary indication of anthropogenic background concentrations of PFAS in shallow soils in England. We retrieved 25 archive samples and collected nine contemporary samples from the same geographical location as their paired archive counterpart. Samples were analysed for 53 PFAS with limits of quantification between 0.1 and 0.5 μg/kg dry weight (dw). The results showed that archive samples contained lower concentrations (mean ∑PFAS-53, 1 μg/kg dw) than paired contemporary soil samples (mean ∑PFAS-53, 3 μg/kg dw). The concentrations reported by this study were similar to other surveys at international, national and regional scales. Our study showed that PFAS were detected in both archive and contemporary field samples. Contemporary field samples should be used as the primary sample type in future research on background concentrations of PFAS in soils. Archive samples have the potential provide complimentary temporal and compositional insights to support the derivation of background concentrations.

PMID:40355067 | DOI:10.1016/j.envpol.2025.126401

Environ Pollut. 2025 May 10;376:126414. doi: 10.1016/j.envpol.2025.126414. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are environmental contaminants including in wildlife but are a fraction of the growing 1000s of PFAS that are being produced. Our study objective was to determine and compare PFAS profiles using targeted analysis and non-targeted analysis (NTA) methods in European starling (Sturnus vulgaris) eggs collected in April/May of 2023 from 11 nesting box sites across Canada at locations described as landfills, near parks, forest, urban, near wastewater facilities, rural, waste management facilities and urban industrial. NTA revealed 41 PFAS at variable detection frequencies in eggs samples and up to 29 PFAS were quantifiable by targeted method analysis. The Σ₂₉PFAS mean concentration (range) (1048 (991-1078) ng/g ww) at the lone landfill site at Brantford were the highest whereas all other sites were <151 ng/g w.w. Σ₂₉PFAS concentrations were not significantly different (p < 0.05) among the 10 non-Brantford landfill sites including the Nova Scotia hospital site (range of 58.0-152 ng/g ww). Two side-chain fluorinated polymer surfactants for a sub-set of egg pools, and 4 emerging PFAS including GenX (or HFPO-DA), F-53B components and ADONA for all pools were not detectable. Confirmed against in-house synthesized standards, 8:2 FTOH sulfate, was detected in 93 % of all samples, and 6:2, 10:2, and 12:2 FTOH sulfates were also detected only in Brantford landfill site eggs. FTOHs, which are likely precursors of FTOH sulfate metabolites, were not detectable in any samples. This suggested that FTOH sulfate metabolites may be suitable biomarkers of exposure to FTOHs and perhaps other PFAS. Among all nest box locations, other additional NTA detected PFAS in eggs were e.g. branched isomers of PFOA, PFHpS, PFNS and PFDS and 6:2 diPAP. Overall, more targeted PFAS candidates should be monitored in starling eggs.

PMID:40355069 | DOI:10.1016/j.envpol.2025.126414

Ecotoxicol Environ Saf. 2025 May 10;298:118293. doi: 10.1016/j.ecoenv.2025.118293. Online ahead of print.

ABSTRACT

The extensive use of perfluoroalkyl substances (PFASs) has raised significant concerns regarding their adverse environmental implications. However, the understanding of their behaviors and biological effects in natural estuarine ecosystems remain limited. This study employed a multidisciplinary approach integrating chemical analysis, biological sequencing, and statistical modeling to comprehensively investigate the distribution of PFASs, as well as their intrinsic relationship with microbial community in the Pearl River Estuary (PRE), a rapidly urbanized area. Our findings demonstrate that the total PFAS concentrations ranged from 52-127 ng L^-1 in water, and 2-70 μg kg^-1 dry weight in sediment, with notably distinct compositions across habitats. Aquatic microbial communities exhibited higher sensitivity to environmental variables, including PFAS concentrations, attributed to increased stochasticity and reduced spatial turnover. Conversely, sediments harbored microbial communities with higher phylogenetic diversity, rendering them less susceptible to PFAS-induced stress. Furthermore, PFAS concentrations significantly affected microbial carbon, nitrogen, and phosphorus cycling, predominantly through indirect alterations in characteristic genus composition. Importantly, noteworthy variations in impacts were observed between perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonic acids (PFSAs), which might contingent upon C-F bond dissociation energies. The findings shed light on PFAS ecological roles and interaction patterns with microbial communities in human-impacted estuarine environments.

PMID:40349469 | DOI:10.1016/j.ecoenv.2025.118293

Environ Pollut. 2025 May 9:126412. doi: 10.1016/j.envpol.2025.126412. Online ahead of print.

ABSTRACT

Emerging contaminants (ECs) have been recognized as a new class of water contaminants and their occurrence in surface water is a concern for ecosystems and society. The aim of this study is to provide a comprehensive systematic review based meta-analysis of ECs in global surface waters and associated ecological risks. With a special focus on pharmaceuticals and illicit drugs (PIDs), and per- and polyfluoroalkyl substances (PFAS). Web of Science, Scopus, Google Scholar, and PubMed databases were screened to retrieve articles published between 2013 and 2024. One hundred-one articles comprising 714 datasets spanning 70 PIDs and PFASs in surface water across 46 countries were included in the meta-analysis study. Global PID concentrations ranged from 0.02 ng/L to 82,188 ng/L, with metformin (MFN) having the highest meta-analyzed median concentration of 729.4 ng/L. Antibiotics, analyzed separately revealed sulfonamides as the most detected. Our analysis showed that PIDs (including antibiotics) levels were in the upper quartiles in low-income settings where wastewater treatment is scarce, whereas in most situations where secondary treatments are utilized, their levels tended to remain in the lower quartile. Wastewater treatment beyond a secondary level can reduce these chemicals to levels which present little to no environmental impact. Global PFAS concentrations ranged from 0.01 ng/L to 311.25 ng/L with perfluoroalkylcarboxylic acids (PFCAs) being the most commonly occurring PFAS. Meta-analysis revealed that perflurohexanoic acid (PFHxA) had the highest meta-synthesized median concentration of 3.6 ng/L in surface waters. Environmental risk assessment revealed high risk (HQ ≥ 1) for the following: MFN, acetaminophen (APAP), ibuprofen (IBU), sulfacetamide (SAM) and lomefloxacin (LFX) and moderate risk (HQ ≥ 0.1) for perfluorododecanoic acid (PFDoA), perfluorotetradecanoic acid (PFTeDA) and perfluoroundecanoic acid (PFUnDA).

PMID:40349823 | DOI:10.1016/j.envpol.2025.126412

Environ Res. 2025 May 9;279(Pt 1):121806. doi: 10.1016/j.envres.2025.121806. Online ahead of print.

ABSTRACT

Due to their high emission and persistence, per- and polyfluoroalkyl substances (PFAS) are ubiquitously distributed in the environment, with soil increasingly serving as a major medium for PFAS. Currently, research on the environmental distribution of PFAS primarily focuses on surface water and groundwater, while systematic global investigations into PFAS distribution in soil remain limited. In this study, we collected PFAS concentrations data from literatures published in 2006-2024 and Map of Forever Pollution in Europe. PFAS concentrations in global soil exhibited spatial heterogeneity (n.d. - 1838 ng/g), with relatively higher levels in Europe, the U.S., and Eastern China. For temporal trend, PFOA, PFHxS, and PFOS generally decreased in the time span of 2005-2019, but the declining trend was relatively sharper in the U.S. compared with China. The meta-analysis indicated that soil properties, including soil texture, organic carbon content, total nitrogen content, and pH, as well as socioeconomic levels such as GDP per capita, per capita consumption expenditure, population density, and industrial proportions, were key factors affecting the distribution of PFAS in soil. Emerging PFAS showed regional differences in detection frequencies, with HFPO-DA (63.84 %-100 %) and 6:2 Cl-PFESA (69.38 %-100 %) predominating in China, 6:2 FTAB (78 %) in the U.S, PreFOSs and PAPs (90 %-100 %) in Europe. This study provides information on the current status of PFAS pollution in soil and key factors affecting its regional distribution, which is beneficial for strengthening the investigation of PFAS soil pollution in areas with less research and developing control and management strategies for high pollution areas.

PMID:40350011 | DOI:10.1016/j.envres.2025.121806

Environ Res. 2025 May 9;279(Pt 2):121766. doi: 10.1016/j.envres.2025.121766. Online ahead of print.

ABSTRACT

The occupation of firefighting is classified as a Group 1 carcinogen. Increased cancer risk among firefighters may be partly attributable to increased occupational exposure to a range of chemicals, including per- and polyfluoroalkyl substances (PFAS). Some PFAS are known and suspect human carcinogens. Investigating epigenetic response to these PFAS exposures in firefighters may help to identify biological pathways of specific cancers, and previously unidentified health outcomes that are associated with PFAS. We therefore investigated the associations of serum PFAS concentrations with miRNA expression in firefighters. Serum samples collected from 303 firefighters from 6 sites across the USA were analyzed for 9 PFAS along with miRNA expression. Covariate-adjusted linear regression was used to estimate associations between log PFAS and miRNA expression, with false discovery rate (FDR) set to 0.05 for significance, and an exploratory cutoff of FDR q < 0.20. Gene set enrichment analysis (GSEA) was performed using miRTarBase's miRWalk pathways. Age, race-ethnicity, BMI, fire department, and sex were controlled for in all models. At FDR<0.05, the linear isomer of perfluorooctane sulfonic acid (PFOS) was inversely associated with miR-128-1-5p expression (Beta = -0.146, 95 % CI -0.216, -0.076). At a relaxed FDR of 0.20, we observed inverse associations for the sum of branched isomers of PFOS (Sm-PFOS) with 5 miRNAs (let-7d-5p, let-7a-5p, miR-423-5p, let-7b-5p, miR-629-5p). Several pathways were enriched for multiple PFAS, including those correlated with certain cancers, blood diseases, thyroid disorders, autoimmune disorders, and neurological outcomes. Some PFAS in firefighters were found to be associated with alteration of miRNA consistent with increased risk for a range of chronic diseases.

PMID:40350013 | DOI:10.1016/j.envres.2025.121766

Environ Res. 2025 May 9;279(Pt 2):121814. doi: 10.1016/j.envres.2025.121814. Online ahead of print.

ABSTRACT

BACKGROUND: Prenatal exposure to poly- and perfluoroalkyl substances (PFAS) has been associated with lower birth weight or increased adiposity in adolescence. No study has investigated associations with longitudinal growth from conception to early childhood. We explored the association between maternal serum PFAS concentrations during pregnancy and child growth assessed repeatedly from the second trimester of pregnancy to 3 years of age.

METHODS: In the SEPAGES cohort, for 450 pregnant women recruited before 19 gestational weeks in Grenoble (France), we measured 26 PFAS from non-fasting maternal serum samples (median gestational age at sampling: 19.4 weeks). Cluster-based analysis identified three PFAS exposure groups (low, moderate, high). Child growth parameters (weight, height, and head parameters) were measured at second and third trimesters (ultrasound examinations), at birth and until 3 years. Using a nonlinear mixed model, we predicted growth parameters and velocities at exactly 3 months and 3 years.

RESULTS: Compared to children belonging to the low PFAS exposure group, those belonging to the high exposure group had higher head circumference during the second trimester (β [95 % CI] = 3.60 [1.49 to 5.72] mm) and at 3 years (39.85 [1.62 to 78.08] mm) as well as higher estimated fetal weight during the second trimester (15.85 [1.48 to 30.21] g) and BMI growth velocity at 3 years (9.66 [1.73 to 17.59] g/m²/month). PFAS concentrations were not associated with growth parameters at third trimester, birth and 3 months.

CONCLUSIONS: In this prospective study, maternal serum PFAS concentrations were associated with some child growth parameters, potentially associated with increased risk of obesity in later-life.

PMID:40350015 | DOI:10.1016/j.envres.2025.121814

Water Res. 2025 May 7;283:123792. doi: 10.1016/j.watres.2025.123792. Online ahead of print.

ABSTRACT

The demand for effective remediation of aqueous per- and polyfluoroalkyl substances (PFAS), especially emerging PFAS, has constantly increased over the last few years. Although adsorption and coagulation are well-established techniques for PFAS remediation, adsorption reaction requires a long equilibrium time; coagulation performance deteriorates when PFAS concentration becomes lower. To address the challenges, an integrated approach which synergistically combined adsorption and coagulation was proposed in this study, using perfluorononenoxybenzenesulfonate (OBS) as the target emerging PFAS to evaluate performance. Ultrafine magnetic hydrotalcite (Fe₃O₄@LDHs), synthesized via a simple ball-milling process, served as the adsorbent in this approach. Such ultrafine material not only enhanced floc formation during coagulation but also showed rapid OBS adsorption via anion exchange. Cationic Polyacrylamide (CPAM) as the optimal coagulant contributed to OBS removal through electrostatic attraction driven by [R₄N⁺] groups and hydrophobic interactions involving its alkyl chains. Under optimal dosage of CPAM (25 mg·L^-1) and Fe₃O₄@LDHs (50 mg·L^-1), the combined magnetic coagulation process achieved 99.89 % of OBS removal within 30 mins. Such combined method still showed effective performance in the presence of hydrocarbon organic competitors, achieving above 90 % removal of OBS from firefighting training wastewater with an acceptable dosing increase. The adsorption-coagulation technique provides a promising and fast solution for treating PFAS wastewater, such as firefighting and industrial wastewater.

PMID:40349599 | DOI:10.1016/j.watres.2025.123792

Chemosphere. 2025 Jun;380:144458. doi: 10.1016/j.chemosphere.2025.144458. Epub 2025 May 9.

ABSTRACT

This study evaluated the trends of 44 water quality parameters by using a bench-scale rotary evaporator to evaporate three landfill leachates and two synthetic leachates. The concentrations of total dissolved solids (TDS), total suspended solids (TSS), chemical oxygen demand (COD), total organic carbon (TOC), five-day biochemical oxygen demand (BOD₅), zinc, chromium, and most per- and polyfluoroalkyl substances (PFAS), including fluorotelomer sulfonates (FTSs), perfluoroalkyl carboxylic acids (PFCAs), and perfluorosulfonic acids (PFSAs), increased in all three landfill leachate residuals during evaporation. On the contrary, the concentrations of volatile compounds including ammonia, naphthalene, p-cresol, pyridine, and fluorotelomer alcohols (FTOHs) decreased in the residuals. Ammonia was first transferred to the condensates and then to the vapor phase. All naphthalene was transferred to the vapor phase. The majority of p-cresol (81-93 % in mass) was transferred to the condensates. Pyridine ended in both the vapor phase (21-53 % in mass) and the condensates (47-79 % in mass). Aniline and phenol were produced during the evaporation. More than 99.9 % of each FTOH in mass was removed from the residual and condensate. PFCAs mainly remained in the leachate residual, with only 0.138-6.83 % (in mass) of PFCAs transferred to condensate.

PMID:40347668 | DOI:10.1016/j.chemosphere.2025.144458

Lipids Health Dis. 2025 May 10;24(1):174. doi: 10.1186/s12944-025-02582-x.

ABSTRACT

BACKGROUND: The widespread presence of per-and polyfluoroalkyl substances (PFAS) has raised global health concerns. This study aims to determine the age-specific relationships of PFAS compounds with metabolic syndrome (MetS) and its components.

METHODS: We used data from the National Health and Nutrition Examination Survey (NHANES) in 2003-2018. Modified Poisson regression was employed to estimate associations between individual PFAS compounds and prevalence of MetS, as well as its components. Multiple linear regression analyses were performed to examine the associations between PFAS congeners and metabolic markers, including lipid and glucose homeostasis traits. Additionally, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were conducted to investigate the joint effects of PFAS mixtures on the prevalence of MetS and its components across different age groups.

RESULTS: A total of 5850 participants were included for analysis. In the Modified Poisson regression model, ln-transformed perfluorononanoic acid (PFNA) level was positively correlated with MetS prevalence in adolescents (prevalence ratio [PR] = 1.42; 95% CI: 1.01-1.99). Conversely, ln-transformed perfluorohexanesulfonic acid (PFHxS) and ln-transformed 2-(N-Methylperfluorooctane sulfonamido) acetic acid (MeFOSAA) were negatively associated with the risks of MetS in young adults (PR = 0.86, 95% CI: 0.76-0.98) and middle-aged adults (PR = 0.88, 95% CI: 0.79-0.98), respectively. Notably, individual PFAS exposure was positively associated with levels of total cholesterol, low-density lipoprotein, non-high-density lipoprotein, and high-density lipoprotein in young and middle-aged adults. However, overall effect analyses using WQS and BKMR showed no significant associations of PFAS mixture with MetS in any age group. Nonetheless, in middle-aged adults, PFAS mixture was adversely correlated with hypertriglyceridemia and positively linked to a greater risk of hypertension and increased high-density lipoprotein cholesterol levels.

CONCLUSIONS: Our study highlighted the complex relationships between PFAS exposure and the risks of MetS and its components across different age groups. Co-exposure to PFAS was particularly linked to dyslipidemia in young and middle-aged adults. Prospective studies are needed for better comprehension of the causative impact of PFAS on the risks of MetS.

PMID:40349075 | PMC:PMC12065354 | DOI:10.1186/s12944-025-02582-x

Toxicol Sci. 2025 May 10:kfaf066. doi: 10.1093/toxsci/kfaf066. Online ahead of print.

ABSTRACT

BACKGROUND: Exposure to pollutants including the ubiquitous 'forever chemical', Perfluorooctane sulfonate (PFOS) has increasingly been associated with metabolic dysfunction-associated steatotic liver disease (MASLD). Recent epidemiological evidence has identified associations between Per- and polyfluoroalkyl substances (PFAS) exposure and increased liver injury in alcohol consumers, suggesting potential interactions between these exposures. However, the intersection of pollutant exposures and alcohol-associated liver disease (ALD) is not well studied. We hypothesize that pollutants may disrupt hepatic metabolism to modify ALD severity. Recently, we developed a two-hit (ethanol plus pollutant) mouse model, enabling testing of this hypothesis. Here, we elucidate the metabolic and disease-modifying effects of PFOS in this model.

METHODS: Male C57BL/6J mice were fed isocaloric control or 5% Ethanol (EtOH) Lieber-DeCarli diet for 15 days. From day 6 of feeding, mice were concurrently gavaged with 1 mg/kg PFOS or 2% tween-80 vehicle for 10 days, followed by a 5 g/kg EtOH binge dose and euthanized 5-6 hours later.

RESULTS: Approximately 60% of the administered PFOS dose accumulated in liver. PFOS exacerbated EtOH-induced hepatic steatosis and was associated by higher levels of plasma very low-density lipoprotein (vLDL) and alanine aminotransferase (ALT). PFOS upregulated hepatic ethanol-metabolizing enzymes and lowered blood alcohol levels. Ingenuity Pathway Analysis (IPA) Top Toxicity Functions/Lists associated with hepatic gene expression following PFOS co-exposure in EtOH-fed mice included: Fatty acid metabolism and liver steatosis; nuclear receptor activation, cytochrome P450, and reactive oxygen species (ROS); apoptosis; liver fibrosis; and hepatocellular carcinoma (HCC). GO/KEGG analyses similarly revealed enrichment in fatty acid, xenobiotic, alcohol, or glutathione metabolic processes; and Peroxisome proliferator-activated receptor (PPAR) signaling. PFOS upregulated hepatic expression of several nuclear receptors (e.g., Pparα, Car, and Pxr) and their P450 target genes (e.g., Cyp4a10, Cyp2b10, and Cyp3a11) by RT-PCR or Western blot, confirming key IPA predictions.

CONCLUSIONS: PFOS is a metabolism disrupting chemical that worsened ALD severity. PFOS activated hepatic nuclear receptors and enriched hepatic transcriptional pathways associated with steatosis, xenobiotic metabolism, oxidative stress, cell death, fibrosis, and HCC. These data demonstrate a novel mechanism whereby PFOS exacerbates ALD through coordinated dysregulation of lipid homeostasis and liver injury, potentially mediated by nuclear receptor activation. The identification of PFOS as an ALD risk modifier highlight the critical need to evaluate environmental pollutants as potential contributors to liver disease progression. More data are required on environmental pollution as a disease modifying factor in ALD.

PMID:40347464 | DOI:10.1093/toxsci/kfaf066

J Hazard Mater. 2025 May 4;494:138498. doi: 10.1016/j.jhazmat.2025.138498. Online ahead of print.

ABSTRACT

Activated carbon (AC) filtration is an effective technique to remove emerging contaminants in drinking water treatment plants. Adsorption onto AC and biodegradation by biofilm are two main mechanisms for the removal of emerging contaminants such as antibiotics. However, the effects of highly bioaccumulative and toxic poly- and perfluoroalkyl substances (PFAS) on antibiotic removal by AC filtration have not been well-understood. In this work, two AC columns were built and operated for 434 days to study the effects of ng-level PFAS on the removal of sulfamethoxazole (SMX). The results showed that 100 ng/L PFAS significantly decreased the removal rate of 1 μg/L SMX from 78.8 % to 71.7 %. Trace PFAS decreased the abundances of ammonia monooxygenase and nitrite-oxidizing bacteria, thus repressing nitrification co-metabolism process. Meanwhile, trace PFAS inhibited tricarboxylic acid (TCA) cycle by preventing pyruvate from generating acetyl-CoA, reducing energy supply for co-metabolism process. On the other hand, inhibiting TCA cycle led to a redirection of carbon from growth into polysaccharide intercellular adhesin biosynthesis. Trace PFAS also increased glutamate synthase and glutamine synthetase abundances, which promoted biofilm formation and then hindered SMX adsorption by AC. This study provides new insights into the adverse role of PFAS in antibiotic removal by AC filtration.

PMID:40347615 | DOI:10.1016/j.jhazmat.2025.138498

Environ Pollut. 2025 May 8;376:126388. doi: 10.1016/j.envpol.2025.126388. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) have attracted global attention because of their persistence, toxicity, bioaccumulation potential, and associated adverse effects. As important primary producers, freshwater algae constitute the base of the food web in freshwater aquatic ecosystems. However, the effects of key environmental factors on PFAS uptake and bioaccumulation in freshwater algae have not been thoroughly studied. In this study, three bioaccumulation experiments were conducted to evaluate the influence of dissolved cations, dissolved organic carbon, and exposure concentrations on PFAS bioaccumulation in algae. Among the 14 studied PFAS, seven long-chain PFAS tended to bioaccumulate in algae. Elevated divalent cations (Ca²⁺ and Mg²⁺) and dissolved organic carbon did not significantly change the algal bioconcentration factors (BCFs) of PFAS, suggesting complexity of the interactions among PFAS, environmental factors, and biotic activities. Additionally, increasing exposure concentrations (0.5, 1, 5, and 10 μg/L of each PFAS) increased PFAS concentrations in algae but decreased the BCF values. This indicated that attention should be paid to the application of BCFs in future studies, including ecological risk assessment. Moreover, fluorotelomer sulfonic acids (FTSs) were incompletely recovered, suggesting that biotransformation occurred. Further studies should be conducted to evaluate whether algae play a role in FTSs biotransformation and to determine the mechanisms. Studying the impacts of key environmental factors on PFAS bioaccumulation in algae is crucial for understanding the bioaccumulation processes that occur at the lowest trophic level and that eventually affect the dynamics of entire aquatic ecosystems.

PMID:40348273 | DOI:10.1016/j.envpol.2025.126388

Am J Ind Med. 2025 May 8. doi: 10.1002/ajim.23732. Online ahead of print.

ABSTRACT

OBJECTIVES: Nonalcoholic fatty liver disease (NAFLD) is a major public health problem and the most common chronic liver disease today. In Korea, the prevalence and incidence of NAFLD are currently very high, causing a serious social burden. Perfluoroalkyl substances (PFAS) have been consistently implicated as a potential cause of NAFLD, but research in Koreans is limited.

METHODS: Using data from the 4th Korean National Environmental Health Survey (KoNEHS, n = 2859), we investigated the association between PFAS blood levels and NAFLD. Multivariable logistic regression models were used to calculate odds ratios (ORs) for the effects of PFAS. A mediation analysis was also conducted to examine the mediating effect of obesity. Finally, weighted quantile sum (WQS) and G-computation methods were implemented to evaluate the joint effect of PFAS mixtures. Hepatic steatosis index was used as a diagnostic tool for NAFLD.

RESULTS: Through multivariable logistic regression, statistically significant associations with NAFLD were observed for perfluorooctanoic acid (PFOA) (OR 1.09-1.39), perfluorooctansulfonate (PFOS) (1.09-1.40), perfluorohexanesulfonic acid (PFHxS) (1.04-1.22), perfluorononanoic acid (PFNA) (1.12-1.42), and total PFAS (1.21-1.81). We also found that obesity was a significant mediator for PFOA, PFNA, and total PFAS. The ORs for NAFLD obtained by WQS and G-computation methods in the multivariable adjusted model were 1.10-1.46 and 1.08-1.32, respectively.

CONCLUSIONS: This study confirmed a significant association between some PFAS and increased odds of NAFLD. Excessive exposure to PFAS might explain the high prevalence and incidence of chronic liver disease in Koreans. Long-term cohort studies are needed to assess geographic and occupational exposures in the Korean population.

PMID:40341549 | DOI:10.1002/ajim.23732

Ecotoxicol Environ Saf. 2025 May 8;298:118273. doi: 10.1016/j.ecoenv.2025.118273. Online ahead of print.

ABSTRACT

BACKGROUND: Ubiquitous perfluoroalkyl/polyfluoroalkyl substances (PFASs) exhibit sex-differential blood accumulation. However, sex- and age-specific links between PFASs and insulin-hormone dysregulation remain unknown.

METHODS: This population-based study utilized survey-weighted data from the National Health and Nutrition Examination Survey 2013-2016. Correlations between PFASs and sex hormone- or insulin-related indicators were assessed using a survey-weighted generalized linear model (SWGLM) for individual analyses and weighted quantile sum (WQS) regression for mixture analyses, stratified by sex and age. The mixture-related findings were validated with Bayesian kernel machine regression (BKMR) and further examined through stratification by menopausal status. Moreover, we investigated whether homeostatic model assessment of insulin resistance (HOMA-IR) mediated the relationships between sex hormones and monomethyl branched isomers of perfluorooctane sulfonate (Sm-PFOS) sex-specifically.

RESULTS: The following results persisted only in females. In SWGLM, linear perfluorooctanoate (n-PFOA) and homeostatic model assessment of β cell function (HOMA-β) were positively correlated in females, with this correlation strengthening in those aged ≥ 60. In WQS, PFAS mixture was positively associated with total testosterone/estradiol (TT/E₂) and negatively associated with estradiol (E₂) in females, but not in postmenopausal participants; the BKMR demonstrated trends consistent with prior findings. These associations intensified in females aged 20-59, with n-PFOA and perfluorohexane sulfonic acid (PFHxS) being main pollutants in the 20-39 and 40-59 age groups, respectively in WQS. The relationships between Sm-PFOS and both free androgen index and sex hormone-binding globulin (SHBG) were mediated by HOMA-IR.

CONCLUSIONS: This cross-sectional study reveals female-specific associations between PFASs and insulin-hormone imbalance, suggesting multifaceted influences of PFASs on female endocrinology.

PMID:40344783 | DOI:10.1016/j.ecoenv.2025.118273

J Hazard Mater. 2025 May 5;494:138506. doi: 10.1016/j.jhazmat.2025.138506. Online ahead of print.

ABSTRACT

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are highly stable man-made chemicals. They have recently garnered significant attention due to their ubiquitous presence in the environment and deleterious effects on human health including cardiovascular diseases (CVDs). Thrombosis due to platelet activation is a major aspect in CVDs. However, the direct effect and underlying mechanism of PFAS on the platelets remains elusive. Here, we observed that PFAS engagement with the extracellular domain of platelet GPIbα, transduced GPIbα-driven inward signals, resulting in intracellular calcium mobilization, activation of Akt and αⅡbβ3 integrin, culminating in platelet aggregation and procoagulant platelet formation. PFAS pretreatment enhanced GPIb-mediated platelet spreading and thrombus formation under high shear conditions. PFAS-induced platelet activation was markedly decreased in Gpibα-deficient mice. PFAS-primed platelets drove neutrophil extracellular traps formation through GPIbα-dependent pathway. Further, PFAS-exposed mice showed heightened risk of thrombus growth and ischemic stroke. Our findings provide experimental evidence for the causal links between PFAS exposure and thrombotic CVDs. Blockade of GPIbα and the downstream pathways could be an instrumental strategy against PFAS-induced platelet activation and thrombosis.

PMID:40344836 | DOI:10.1016/j.jhazmat.2025.138506

Aquat Toxicol. 2025 Jul;284:107395. doi: 10.1016/j.aquatox.2025.107395. Epub 2025 May 4.

ABSTRACT

Perfluorodecanoic acid (PFDA), a long-chain perfluoroalkyl substance (PFAS), is known for its environmental persistence and potential toxicity. This study evaluated PFDA toxicity in the RTgill-W1 cell line, a model for aquatic toxicology, using a combination of cell viability assays, reactive oxygen species (ROS) measurements, and high-throughput metabolomics and lipidomics. PFDA exposure resulted in significant, dose-dependent reductions in cell viability and increased ROS production, with an EC₅₀ value of 51.9 ± 1.7 mg/L, highlighting its cytotoxic potential. Metabolomic profiling revealed dose-dependent disruptions in 168 metabolites, impacting pathways related to amino acid metabolism, carbohydrate metabolism, lipid metabolism, vitamin and cofactor metabolism, and nucleotide metabolism. Furthermore, lipidomic analysis identified 102 significantly altered lipids, primary affecting glycerolipid metabolism, fatty acid biosynthesis, glycerophospholipid metabolism, sphingolipid metabolism - suggesting compromised membrane integrity, energy production, and signalling processes. These findings underscore PFDA's capacity to interfere with critical cellular processes and highlight the utility of integrated omics approaches in elucidating the molecular mechanisms of PFAS toxicity. Future studies should focus on validating fish cell assays through short-term in vivo tests to enhance their reliability and ecological relevance.

PMID:40344972 | DOI:10.1016/j.aquatox.2025.107395

Environ Pollut. 2025 May 8;376:126400. doi: 10.1016/j.envpol.2025.126400. Online ahead of print.

ABSTRACT

This study aims to investigate the distribution of per- and polyfluoroalkyl substances (PFAS) and their precursors in 55 consumer products, including 27 personal care products (PCPs) from 7 categories and 28 household products (HPs) from 6 categories and analyze the correlation between them, by measuring PFASs using target analysis with LC-MS/MS and suspect screening using high-resolution mass spectrometry (HRMS) combined with ion mobility separation (IMS). In most products, perfluorocarboxylic acid (PFCA) concentrations (0.036-25.2 ng/g) exceeded perfluorosulfonic acid concentrations (n.d.-0.566 ng/g). In PCPs, the median concentrations of 12 PFASs and two fluorinated precursors (0.053-139 ng/g) were significantly higher than in HPs (0.012-76.0 ng/g) (p < 0.05). Across all PCP and HP types, short-chain PFASs (PFCAs ≤ C7; PFSAs ≤ C6) (1.68-46.9 ng/g) were also significantly higher than long-chain PFASs (0.071-6.86 ng/g) (p < 0.05). Suspect screening identified a total of 9 candidate PFASs, including the four PFCA precursors, all of which were assigned a confidence level of 3 or higher. The observed positive correlation between precursors and PFCAs (p < 0.05) suggests that precursors may be converted into PFCAs, thereby increasing PFCA concentrations, although the specific transformation pathways require further investigation. This study provides insights into the distribution of PFAS and their precursors in consumer products and demonstrates that IMS-HRMS-based suspect screening can be useful for distinguishing false positives in PFAS identification.

PMID:40345370 | DOI:10.1016/j.envpol.2025.126400

Environ Int. 2025 May;199:109520. doi: 10.1016/j.envint.2025.109520. Epub 2025 May 9.

NO ABSTRACT

PMID:40345863 | DOI:10.1016/j.envint.2025.109520

Sci Rep. 2025 May 9;15(1):16241. doi: 10.1038/s41598-025-01128-6.

ABSTRACT

Studies have demonstrated that point source emissions constitute the main direct source of PFASs in water. However, if production/usage and emission from a specific point are stopped, does the point source still present a threat to surrounding waters? In this study, the occurrence and potential human exposure to 17 PFASs in the surrounding ambient river and ground/drinking water within a 13 km around the facility were assessed. Of the 17 PFASs analyzed, 11 were frequently detected in river and groundwater samples, with perfluorobutane sulfonate (PFBS) (36.8-11462.9 ng/L), perfluorobutyric acid (PFBA) (below the detection limit (BDL)-4789.8 ng/L) and perfluorohexane sulfonate (PFHxS) (3.3-3549.0 ng/L) exhibiting the highest concentrations. Prevalence of short-chain PFASs was observed in both river and groundwater. The spatial distribution pattern showed that locations near the facility exhibited higher PFASs concentrations. The seasonal distribution pattern indicated that the PFASs concentration in river water during the wet season was higher than that during the dry season. However, the seasonal distribution in groundwater was unexpectedly the opposite to that in river water. Nevertheless, the major health risk of PFASs is primarily attributed to the presence of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) with maximum hazard quotients of 6.9 × 10² and 1.0 × 10³ and 2.4 and 3.6 for adults and toddlers, respectively. Thus, the potential threat of the closed fluorochemical manufacturing plant to the surrounding waters cannot be ignored.

PMID:40346148 | PMC:PMC12064658 | DOI:10.1038/s41598-025-01128-6

Alzheimers Dement. 2025 May;21(5):e70226. doi: 10.1002/alz.70226.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous persistent organic pollutants. The neurotoxic and cardiometabolic effects of PFAS are well documented, leading to the hypothesis that exposure increases dementia risk. However, empirical data on PFAS in relation to cognitive impairment and dementia are weak, limited, and inconsistent. This report reviews the literature on PFAS and cognitive impairment and provides a rationale and overview of the PFAS VascCog Longitudinal Study, a new study using the population-based Northern Manhattan Study cohort, to prospectively examine serum concentrations of 13 PFAS in relation to lipids, carotid atherosclerosis, cognitive impairment, and dementia. We hypothesize that PFAS deleteriously impact cognition through a pathway involving hyperlipidemia and atherosclerosis. Rigorous examination of PFAS exposure in relation to dementia is needed to inform public health policies on PFAS-containing products, support regulations to reduce community exposure, and provide new avenues to protect cognitive health and impact dementia at the individual and community levels. HIGHLIGHTS: PFAS exposure increases cardiometabolic risk factors and neurotoxicity. Data on PFAS in relation to cognitive health is limited, weak, and controversial. We hypothesize that PFAS exposure increases dementia risk. We hypothesize a mechanistic pathway involving hyperlipidemia and atherosclerosis. Rigorous study of PFAS exposure and dementia risk can inform public health policy.

PMID:40346447 | PMC:PMC12064343 | DOI:10.1002/alz.70226

Org Lett. 2025 May 9. doi: 10.1021/acs.orglett.5c01492. Online ahead of print.

ABSTRACT

The defluorination of trifluoromethyl groups typically involves breaking one or all three C-F bonds, while selectively cleaving exactly two C-F bonds presents a considerable challenge. In this work, we present a method for the sequential defluorination of trifluoromethyl hydrazones under photocatalytic conditions, which involves the specific breakage of two C-F bonds followed by thiolation to yield monofluorinated alkenes containing a thiol group. Transforming trifluoromethyl-containing polyfluoroalkyl substances into fluorinated non-PFAS compounds holds potential practical implications.

PMID:40340476 | DOI:10.1021/acs.orglett.5c01492

Vet World. 2025 Mar;18(3):636-645. doi: 10.14202/vetworld.2025.636-645. Epub 2025 Mar 18.

ABSTRACT

BACKGROUND AND AIM: The increasing prevalence of antibiotic-resistant pathogens necessitates the exploration of alternatives to growth-promoting antibiotics (GPAs) in poultry production. This study evaluated a commercial additive containing plant extracts (carvacrol and cinnamaldehyde) as a potential replacement for GPAs in broiler chickens, focusing on productive parameters, cecal microbiota composition, cecal volatile fatty acid (VFA) concentration, and small intestinal histomorphology.

MATERIALS AND METHODS: The study involved 100 one-day-old Cobb 500 broiler chickens, divided into two treatment groups: Group 1 (control) received a basal diet (BD) with avilamycin (100 g/T), and Group 2 received a BD with a phytogenic feed additive (PFA) containing 10% carvacrol and 10% cinnamaldehyde (100 g/Tn). Over 42 days, the study measured total weight gain (TWG), feed intake, feed conversion ratio (FCR), carcass yield, digestive tract length, intestinal histomorphometry, VFA concentration, and cecal microbiota composition.

RESULTS: The PFA-treated group showed a 1.67% improvement in TWG and a 5.7% improvement in FCR compared to the control. The digestive tract length increased by 20 cm with PFA supplementation. While no significant differences were observed in cecal microbiota counts and VFA concentrations, a trend toward increased lactic acid bacteria and VFA levels was noted. Histomorphological analysis indicated enhanced villus height and a higher villus height-to-crypt depth ratio in the PFA group.

CONCLUSION: The findings suggest that carvacrol and cinnamaldehyde-based PFAs may serve as viable alternatives to GPAs, promoting growth performance and gut health in broiler chickens. Further research is needed to elucidate the underlying mechanisms of action and confirm these preliminary results in larger-scale studies.

PMID:40342754 | PMC:PMC12056912 | DOI:10.14202/vetworld.2025.636-645

Environ Sci Technol. 2025 May 20;59(19):9744-9753. doi: 10.1021/acs.est.4c14136. Epub 2025 May 8.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are chemical pollutants of growing concern for many stakeholders. Due to their ubiquity, persistence in the environment, and potential for toxicity at low environmental concentrations, it is necessary to have convenient and reliable methods to measure PFAS in natural waters. Passive sampling methods (in situ preconcentration of PFAS) may be suitable for monitoring situations. One passive sampling design successfully employed for other, well studied contaminants (e.g., methylmercury) is the diffusive gradient in thin film sampler (DGT). However, the application of DGT for PFAS requires development and validation. Here, we iterate on previous PFAS-DGT studies by introducing a redesigned diffusive gradient sampler for PFAS in water and show that it reliably measures 25 PFAS in water, consistent with diffusion theory. Diffusion and whole-sampler uptake rates consistently agreed with model predictions within ±50% relative difference, including when tested at cold temperature (5 °C). In field and laboratory deployments, DGT samplers measured PFAS concentrations within ±23% of grab sample results on average in each case─better performance than codeployed microporous polyethylene tube passive samplers. Based on the evidence in this study, the DGT passive sampler is a promising tool for consistently and accurately passively sampling PFAS in natural waters.

PMID:40338921 | DOI:10.1021/acs.est.4c14136

Environ Int. 2025 May;199:109508. doi: 10.1016/j.envint.2025.109508. Epub 2025 May 3.

ABSTRACT

INTRODUCTION: Per- and polyfluoroalkyl substances (PFAS) have been linked to effects on human lipid profiles, with several epidemiological studies reporting associations between specific PFAS and blood lipid concentrations. However, these associations have been inconsistent, and most studies have focused on cross-sectional analyses with limited repeated measurements.

OBJECTIVE: In this study, we investigated associations between serum PFAS concentrations and major blood lipid classes over a 30-year period (1986-2016) and up to five time points. Lipids analyzed included total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG).

METHODS: This study included 145 participants from The Tromsø Study, Norway, who donated plasma samples three to five times over the study period. Linear mixed-effects (LME) models assessed longitudinal associations between PFAS and lipid classes, while multiple linear regression (MLR) models were used for cross-sectional associations.

RESULTS: LME models demonstrated positive longitudinal associations between perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), and perfluorotridecanoic acid (PFTrDA) with TC. Additionally, PFOA, PFDA, PFUnDA, PFDoDA, and PFTrDA were associated with LDL-C, and PFUnDA and summed perfluorooctane sulfonate isomers (∑PFOS) with HDL-C. Cross-sectional analyses corroborated positive associations between the six PFAS compounds and TC at least three times, but the LDL-C and HDL-C associations were not confirmed. Summed perfluorooctane sulfonamide isomers (∑PFOSA) showed a negative association with LDL-C longitudinally, but this was not confirmed cross-sectionally. No associations were observed between PFAS and TG, longitudinally or cross-sectionally.

CONCLUSION: Concentrations of multiple PFAS were positively associated with blood lipids in longitudinal analyses, with the most consistent associations observed between six PFCA compounds and TC. These findings highlight the need for further investigation into these complex associations.

PMID:40339345 | DOI:10.1016/j.envint.2025.109508

Ann Endocrinol (Paris). 2025 May 6:101775. doi: 10.1016/j.ando.2025.101775. Online ahead of print.

NO ABSTRACT

PMID:40339690 | DOI:10.1016/j.ando.2025.101775

Environ Res. 2025 May 6;279(Pt 2):121795. doi: 10.1016/j.envres.2025.121795. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFASs) are stable synthetic compounds that pose significant risks to humans and tend to accumulate during the biotransformation of municipal waste. Although physical and chemical methods can effectively remove PFASs, their high costs and susceptibility to secondary contamination have limited broader adoption. Microbial degradation of PFASs is an environmentally friendly and cost-effective approach, making it a highly promising method for removing PFASs in municipal waste biotransformation. This paper summarizes recent advancements in the mechanisms of PFASs removal in common waste biotransformation processes, such as composting, anaerobic digestion and biological wastewater treatment. Microorganisms remove PFAS from municipal waste mainly through adsorption and biodegradation. We suggest that the type of PFAS, the coexistence of multiple emerging pollutant and PFAS, and the nutrients provided by municipal waste are the key factors influencing microbial degradation of PFAS. We consider that in situ enrichment of microorganisms capable of degrading PFAS is an effective way to mitigate the inhibitory effect of PFAS on waste biotransformation. Also, the addition of adsorbent materials, the application of voltage, and the addition of quorum-sensing signalling molecules in combination with biodegradation can improve the effectiveness of biodegradation of PFAS. In this study, we look forward to the future research direction to understand the key metabolic pathways of microbial degradation of PFAS using isotope tracer method. This review provides new insights for efficient biotransformation of municipal waste and effective removal of PFAS.

PMID:40340003 | DOI:10.1016/j.envres.2025.121795

Environ Res. 2025 May 15;279(Pt 2):121790. doi: 10.1016/j.envres.2025.121790. Online ahead of print.

ABSTRACT

BACKGROUND: Exposure to perfluoroalkyl substances (PFAS) is concerning because some of these chemicals are associated with health effects. Preadolescents eat more food per body weight and may be more affected by substances in food compared to adults.

OBJECTIVE: Estimate how diet quality and nutrients are associated with concurrently measured PFAS concentrations in Canadian preadolescents.

METHODS: Using data from 157 participants (7-11 years) in a Maternal-Infant Research on Environmental Chemicals follow-up study (2018-2021), we analyzed serum concentrations of 9 PFAS, and derived 2019-Healthy Eating Food Index (HEFI-2019) scores and nutrient intakes from 24-h diet recalls. We used multivariable linear regression to estimate cross-sectional associations between diet and serum PFAS concentrations.

RESULTS: Saturated fat consumption was associated with higher serum perfluorooctanesulfonic acid (PFOS) concentrations. The fruits and vegetables score was associated with higher perfluorodecanoic acid (PFDA), and perfluorononanoic acid (PFNA); similar associations appeared with the HEFI-2019 total score. Percentage of energy intake (%E) from protein was associated with lower perfluorooctanoic acid (PFOA), PFOS, and perfluorohexanesulphonic acid (PFHxS) while %E from fat was associated with higher PFDA and PFOS. Fiber and iron intakes were associated with higher PFHxS. Vitamin D intake was associated with lower PFNA.

CONCLUSIONS: We observed some associations between diet and PFAS. Our findings may be partially explained by toxicokinetics and PFAS presence in Canadian food systems. However, our interpretation is hindered by lack of temporality and potential confounding. Additional investigations which integrate food systems information paired with PFAS concentrations from food and biomonitoring are required.

PMID:40340011 | DOI:10.1016/j.envres.2025.121790

Environ Health Perspect. 2025 May 7. doi: 10.1289/EHP15422. Online ahead of print.

ABSTRACT

BACKGROUND: Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been shown to disrupt normal follicular development and ovulation. However, it is unknown which specific PFAS in follicular fluid negatively impact oocyte development and embryo quality or whether any of the metabolites present in the follicular fluid contribute to these adverse effects.

OBJECTIVES: We conducted a cross-sectional and cohort study to identify specific PFAS with significant adverse effects on embryo quality and their associated modes of action.

METHODS: We enrolled 378 women undergoing assisted reproductive technology (ART) and collected follicular fluid samples during oocyte retrieval. We performed PFAS detection and untargeted metabolomics on the follicular fluid. The association of individual PFAS with high-quality embryo rates and clinical pregnancy outcomes were assessed using beta regression and logistic regression, respectively, and potential joint effect of mixtures of PFAS using Bayesian kernel machine regression (BKMR) and Quantile g-computation models. A causal mediation effect model was performed to estimate the average indirect impact of PFAS, mediated by high-quality embryo rates, on the clinical pregnancy outcomes, as well as its direct impact representing all other causal effects. Spearman's rank correlation coefficient was used to identify the associations between the differentially expressed metabolites and the high-quality embryo rates.

RESULTS: The detection frequencies of 15 PFAS exceeded 85%, and perfluorooctanoic acid (PFOA) had the highest median concentration (6.54 ng/mL). The PFAS mixture was negatively associated with the high-quality embryo rate, and PFOA was the major contributor (conditional posterior inclusion probability = 0.97295). PFAS was also negatively associated with the clinical pregnancy outcome, and the causal mediation analysis revealed that the embryo quality potentially mediated the relationship between the clinical pregnancy outcome with PFOA (proportion mediated: 0.181, 95% CI: 0.024, 0.755), Perfluoro-n-nonanoic acid (PFNA, proportion mediated: 0.148, 95% CI: 0.022, 0.656), or Perfluoro-n-tridecanoic acid (PFTrDA, proportion mediated: 0.130, 95% CI: 0.005, 0.693). The decreased organonitrogens (Pro-Trp and lauryldimethylamine oxide) and sphingolipids metabolites (phytosphingosine, N-myristoylsphinganine and N-lauroyl-d-erythro-sphinganine) in the follicular fluid were associated with PFOA related-poor embryo quality.

CONCLUSIONS: High exposure to follicular fluid PFAS was negatively correlated with embryo quality during ART, with PFOA likely to be the major contributor. PFOA-related poor embryo quality was associated with the reduction of organonitrogens and sphingolipids metabolites that are crucial for the maintenance of normal cell growth and metabolism. https://doi.org/10.1289/EHP15422.

PMID:40334213 | DOI:10.1289/EHP15422

Mar Pollut Bull. 2025 May 6;217:118115. doi: 10.1016/j.marpolbul.2025.118115. Online ahead of print.

ABSTRACT

Laizhou Bay (LZB) is heavily polluted by perfluoroalkyl substances (PFAS), especially perfluorooctanoic acid (PFOA), from the nearby industrial emission. PFOA has been subjected to strict control, leading to the increasing use of PFOA substitutes. However, the present pollution status of PFOA substitutes in the LZB area is unclear. In this study, 14 legacy and 18 emerging perfluoroalkyl substances (PFAS) in surface water and sediment samples from LZB area were investigated. Two homologues of hexafluoropropylene oxide trimer acid (HFPO-TrA (C7 and C8)) were first identified in LZB area. The results revealed that emerging PFAS have overtaken legacy PFAS as the major PFAS contaminants in seawater. Legacy PFAS constituted only ∼13-47 % of the total PFAS concentration (∑PFAS) in the seawater and ∼ 37-68 % of the ∑PFAS in the sediment. PFOA was found to be the major legacy PFAS in both seawater and sediment. Among the emerging PFAS, two series of perfluoropolyether carboxylic acid (PFECA) homologues accounted for 86-97 % of the total emerging PFAS in seawater and 57-96 % of the total emerging PFAS in sediment. The major source of PFAS was point source from the Xiaoqing River for the inner bay area, whereas the outer bay area may receive external input from the Bohai Sea. Although environmental risks were low for legacy PFAS, HFPO homologues as a whole may present high risks in a large area by an optimistic evaluation method. This highlights the urgent research needed for emerging PFAS - especially those PFOA substitutes - in the LZB area.

PMID:40334555 | DOI:10.1016/j.marpolbul.2025.118115

Pediatr Allergy Immunol. 2025 May;36(5):e70104. doi: 10.1111/pai.70104.

ABSTRACT

BACKGROUND: Pollen food allergy syndrome (PFAS) primarily presents as oral allergy syndrome (OAS) with occasional systemic symptoms. Few studies have examined the systemic symptoms of PR-10-related PFAS, which are common among pediatric patients in Japan.

METHODS: Two surveys were conducted to investigate the possibility of more severe patients in medical institutions and misdiagnoses among school children: one for patients diagnosed with PR-10-related PFAS at medical institutions and another for elementary and junior high school children whose parents completed an online questionnaire. We examined allergenic foods/symptoms, incidence of OAS, and systemic symptoms in PR-10-related PFAS patients allergic to Rosaceae fruits/soybeans.

RESULTS: Among 221 patients with PR-10-related PFAS at medical institutions, 205 and 86 developed allergic symptoms to Rosaceae fruits and soybeans, respectively. The incidence of systemic symptoms was significantly higher in the soybean group (43/86, 50.0%) than in the Rosaceae fruits group (43/205, 21.0%) (p < .001). Among the 29,906 school children, 3309 (11.1%) responded; 202 were children with PR-10-related PFAS, 194 and 29 developed allergic symptoms to Rosaceae fruits and soybeans, respectively. The incidence of systemic symptoms was higher in the soybean group (12/29, 41.4%) than in the Rosaceae fruits group (46/194, 23.7%), although not significantly (p = .067).

CONCLUSION: Two surveys were conducted targeting patients with confirmed diagnoses and general students. The incidence of systemic symptoms associated with PR-10-related PFAS was similar at 20% for Rosaceae fruits and 40%-50% for soybeans in both surveys. Attention should be given to the potential for systemic symptoms in patients with PR-10-related PFAS.

PMID:40331464 | DOI:10.1111/pai.70104

Toxicology. 2025 Aug;515:154173. doi: 10.1016/j.tox.2025.154173. Epub 2025 May 5.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants linked to adverse health effects. Epidemiological studies have linked PFAS with an increased risk of uterine diseases including fibroids however, the mechanisms involved remain to be elucidated. This study examined the impact of individual PFAS, such as legacy compounds [perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS)] and alternative short-chain compounds [GENX/HFPO-DA and perfluorobutanesulfonic acid (PFBS)], along with a PFAS mixture, on the function and transcriptome of immortalized human myometrial cells (UT-TERT). Exposure to these PFAS resulted in increased cell viability and proliferation. Flow cytometry showed that PFOS and the PFAS mixture altered cell cycle progression, while migration assays indicated significant enhancement of cell migration following PFOS and mixture exposure. Moreover, PFOA, PFBS, and the PFAS mixture impaired gap junction intercellular communication (GJIC), suggesting possible disruptions in cellular communication in the uterine environment. Transcriptomic analysis identified extensive changes in gene expression after exposure to environmentally relevant PFAS levels, revealing common molecular pathways involved in cell signaling, lipid metabolism, and cell survival. These findings provide crucial insights into how PFAS may contribute to reproductive health risks, warranting further investigation into the long-term effects of PFAS on uterine function and overall reproductive health.

PMID:40334771 | DOI:10.1016/j.tox.2025.154173

Chemosphere. 2025 Jun;380:144462. doi: 10.1016/j.chemosphere.2025.144462. Epub 2025 May 6.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are a class of fluorinated contaminants of concern due to their long environmental persistence, biological uptake and toxicological implications. Mass spectrometry is currently heavily utilized for PFAS analysis and is capable of precise and selective measurements down to parts per trillion (ppt). However, these are labor-intensive laboratory-only methods that require a substantial expertise and specialized equipment, resulting in high cost and long waiting periods which limit their utility in providing rapid, high-quantity and data rich (large number of samples) PFAS contamination screening capability at both local and regional scales. A rapid and fieldable screening method is needed to improve surveying efficiency to enable prioritization of resources where in-depth standard analysis is required. In this manuscript, a novel emulsion extraction methodology is introduced which isolates PFAS from aqueous media. When paired with colorimetric techniques, the method facilitates rapid detection of PFAS at concentrations ranging from part-per-million (ppm) to part-per-trillion (ppt) within minutes; herein, we demonstrate visual (naked eye) colorimetric detection of PFOA below 30 ppt. This semi-quantitative emulsion extraction method represents a new means for concentrating PFAS for both detection and remediation purposes in a cost-effective and scalable manner. The cost to construct the prototype kit used in this study-which is indefinitely reuseable-using commercially sourced components and 3D printed housing was less than $150, with material costs per test of less than $2. When fully developed, the kit may therefore be deployed to facilitate efficient screening for PFAS to expedite assessments in the field or in facilities, allowing for rapid identification of sites requiring more detailed laboratory analysis.

PMID:40334617 | DOI:10.1016/j.chemosphere.2025.144462

Environ Sci Process Impacts. 2025 May 6. doi: 10.1039/d5em00238a. Online ahead of print.

ABSTRACT

To protect human health, limits for the concentrations of per- and polyfluoroalkyl substances (PFAS) in drinking water are decreasing in many countries. However, the required treatment to achieve these lower concentrations is more resource and energy intensive than conventional drinking water treatment. Consequently, this intensified water treatment has an indirect negative impact on human health. For example, treatment with granular activated carbon (GAC), commonly used for PFAS removal, can lead to particulate matter emissions and additional global warming. These negative impacts partly off-set the health benefit achieved by lower PFAS exposure via drinking water. In this study, we quantified health impacts of both the increased treatment and the reduced PFAS exposure in disability-adjusted life years (DALYs), to assess whether PFAS removal from drinking water to specified targets with GAC results in a net health benefit. We selected the prospective Dutch drinking water guideline for PFAS of 4.4 ng PFOA-equivalent (PEQ) L^-1, as this guideline is amongst the more conservative concentration targets globally. We first conducted a Life Cycle Assessment (LCA) to quantify the health cost associated with the increased reactivation frequency of an existing GAC system in the Netherlands, required to achieve PFAS concentrations below 4.4 ng PEQ L^-1. Then, we quantified the health benefit obtained by the corresponding lower PFAS exposure, using pharmacokinetic modelling combined with published dose-response relationships. For the treatment plant investigated in the current study, which uses reactivated wood-based GAC, increasing the reactivation frequency to remove more PFAS was found to result in a net health benefit of 6.9-300 DALYs per 10⁶ persons per year. However, when single-use rather than reactivated GAC would be used for PFAS treatment, the health losses from the GAC production were in the same range as the health benefits from lower PFAS exposure. Overall, the negative health impacts associated with more intensive water treatment should be considered when developing strategies to reduce PFAS exposure.

PMID:40326274 | DOI:10.1039/d5em00238a

Environ Sci Process Impacts. 2025 May 6. doi: 10.1039/d4em00739e. Online ahead of print.

ABSTRACT

Trifluoromethylphenols (TFMPs) are environmental contaminants that exist as transformation products of aryl-CF₃ pharmaceuticals and agrochemicals. Their -CF₃ moiety raises concerns as it may form problematic fluorinated transformation products such as the persistent pollutant trifluoroacetic acid (TFA). This study investigates the hydrolysis and spontaneous defluorination mechanisms of 2-TFMP, 3-TFMP, 4-TFMP, and 2-Cl-4-TFMP under environmentally relevant aqueous conditions, and under alkaline pH to investigate the mechanism of defluorination. 3-TFMP did not undergo hydrolysis. The other TFMPs reacted to primarily form the corresponding hydroxybenzoic acids and fluoride. High-resolution mass spectrometry identified a benzoyl fluoride intermediate in the hydrolysis of 4-TFMP and other dimer-like transformation products of the 4- and 2-Cl-4-TFMP. Density functional theory calculations revealed that the key defluorination step likely proceeds via an E1cb mechanism, driven by β-elimination. Experimental and computational results demonstrated substituent-dependent differences in reactivity, and the importance of the deprotonation of TFMPs for the hydrolysis reaction to proceed. These findings provide mechanistic insights into the complete defluorination of TFMPs and broader implications for the environmental defluorination of other PFAS.

PMID:40326395 | DOI:10.1039/d4em00739e

Environ Sci Technol. 2025 May 20;59(19):9709-9720. doi: 10.1021/acs.est.5c03486. Epub 2025 May 6.

ABSTRACT

Fluoropolymer manufacturing facility (FMF) has been regarded as a main source of perfluoroalkyl and polyfluoroalkyl substances (PFAS) in the atmosphere. In this study, suspect screening was performed to identify emerging PFAS in gas, particles, and dust both inside and outside a large FMF in China. A total of 74 emerging PFAS were tentatively identified with a confidence level of 3 or higher, 32 of which were reported in the environment for the first time. The semi-quantitative concentrations of the emerging PFAS, with perfluoroalkyl ether carboxylic acids (PFECAs) and Cl-PFECAs being predominant, accounted for 21-95% (mean: 46%) of the combined concentrations of emerging and legacy PFAS. Although the PFAS concentrations in the atmosphere decreased rapidly by more than 95% within 5 km, short-chain PFAS in PM_2.5 were transported farther, especially C4 and C5 perfluoroalkyl carboxylic acids, which decreased by 66% and 79% within 5 km, respectively. Emerging PFAS with an ionic terminal group are mainly distributed in the particle phase, while alcohol-related PFAS are found in the gas phase. The ratios of PFAS in the gas phase inside the FMF were much higher than those outside, which could be reasonably explained by the condensation of gaseous PFAS onto fine particles shortly after being emitted.

PMID:40327782 | DOI:10.1021/acs.est.5c03486

J Hazard Mater. 2025 May 2;494:138458. doi: 10.1016/j.jhazmat.2025.138458. Online ahead of print.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants with widespread use and bioaccumulative potential. Short-chain PFAS such as perfluorohexanoic acid (PFHxA) and perfluorohexane sulfonate (PFHxS) have been introduced as safer alternatives to long-chain PFAS, yet their toxicological impacts remain poorly defined. In this study, we employed a 3D Gelatin methacryloyl (GelMA) hydrogel model to mimic the tumor microenvironment and investigated the effects of PFHxA and PFHxS on triple-negative breast cancer (TNBC) progression. At environmentally relevant concentrations (0.1-10 μM), both compounds significantly enhanced proliferation, migration, and invasion of MDA-MB-231 cells. Transcriptomic and machine learning analyses identified MEX3C as a key gene upregulated by PFAS exposure. Gene set enrichment analysis (GSEA) revealed activation of the PI3K-AKT-mTOR signaling pathway, which was further supported by siRNA-mediated knockdown of MEX3C, leading to a marked reduction in the expression levels of phosphorylated PI3K, AKT, and mTOR proteins. Furthermore, immune cell co-culture experiments showed that MDA-MB-231 cells with high MEX3C expression promoted M2 macrophage polarization, suppressed M1 polarization, and enhanced macrophage chemotactic activity, the immunomodulatory effects were significantly attenuated upon MEX3C knockdown. These findings establish MEX3C as a central mediator of PFAS-induced tumor progression and immune remodeling. This study provides mechanistic insight into the carcinogenic potential of emerging short-chain PFAS and underscores the need for stricter regulation to safeguard public health.

PMID:40327938 | DOI:10.1016/j.jhazmat.2025.138458

Environ Int. 2025 May;199:109504. doi: 10.1016/j.envint.2025.109504. Epub 2025 Apr 30.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS), commonly known as "forever chemicals", are ubiquitous in surface waters and potentially threaten human health and ecosystems. Despite extensive monitoring efforts, PFAS risk in European surface waters remain poorly understood, as performing PFAS analyses in all surface waters is remarkably challenging. This study developed two machine-learning models to generate the first maps depicting the concentration levels and ecological risks of PFAS in continuous surface waters across 44 European countries, at a 2-km spatial resolution. We estimated that nearly eight thousand individuals were affected by surface waters with PFAS concentrations exceeding the European Drinking Water guideline of 100 ng/L. The prediction maps identified surface waters with high ecological risk and PFAS concentration (>100 ng/L), primarily in Germany, the Netherlands, Portugal, Spain, and Finland. Furthermore, we quantified the distance to the nearest PFAS point sources as the most critical factor (14%-19%) influencing the concentrations and ecological risks of PFAS. Importantly, we determined a threshold distance (4.1-4.9 km) from PFAS point sources, below which PFAS hazards in surface waters could be elevated. Our findings advance the understanding of spatial PFAS pollution in European surface waters and provide a guideline threshold to inform targeted regulatory measures aimed at mitigating PFAS hazards.

PMID:40328085 | DOI:10.1016/j.envint.2025.109504

Anal Bioanal Chem. 2025 May 5. doi: 10.1007/s00216-025-05886-0. Online ahead of print.

ABSTRACT

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) possess water-repellent, oil-repellent, and heat-resistant properties, making them widely used in consumer goods and industrial products. However, PFASs have been increasingly associated with health concerns, including reproductive toxicity, endocrine disruption, and thyroid disease. In 2023, the US consumer platform "Mamavation" reported organic fluorine levels ranging from 105 to 20,700 ppm in 18 contact lenses, raising concerns about the potential presence of PFASs in these products. Given the absence of established international testing methods and regulatory limits for PFASs in contact lenses, this study evaluated nine standard international methods, ultimately selecting 49 PFASs as target analytes after eliminating overlaps. To facilitate detection, novel extraction methods were developed for contact lenses and their lens care solutions. Ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was employed for analysis, utilizing an analytical column (Atlantis Premier BEH C18 AX, 1.7 µm, 2.1 × 100 mm) and an isolator column (Atlantis Premier BEH C18 AX, 5 µm, 2.1 × 50 mm) to minimize background interference. Electrospray ionization in combination with multiple reaction monitoring mode enabled rapid analysis within 24 minutes. For contact lenses, the limit of quantification (LOQ) ranged from 1 to 400 ng/g, while for lens care solutions, the LOQ ranged from 0.04 to 0.8 ng/mL. When applied to 12 contact lens samples, the method detected 6:2 FTS (1H,1H,2H,2H-perfluorooctane sulfonic acid) in only one lens care solution at a concentration of 0.087 ng/mL. This study highlights the importance of further investigation into PFAS contamination in contact lenses and the need for international standardization in testing methodologies.

PMID:40323375 | DOI:10.1007/s00216-025-05886-0

Biotechnol Lett. 2025 May 5;47(3):48. doi: 10.1007/s10529-025-03593-5.

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants characterized by strong carbon-fluorine bonds, making them resistant to conventional degradation methods. Their widespread detection in soil, water, and living organisms, coupled with significant potential health risks, has necessitated the development of effective remediation strategies. This review provides a detailed overview of recent advances in biotechnological approaches for PFAS degradation, with a focus on microbial and bioelectrochemical systems (BESs). Microbial species such as Pseudomonas and Acidimicrobium strains have demonstrated the ability to degrade PFAS under both aerobic and anaerobic conditions. Key enzymes, including dehalogenases and oxygenases, play a critical role in catalyzing the breakdown of PFAS. BESs technologies, including microbial fuel cells (MFCs) and microbial electrolysis cells (MECs), offer innovative solutions by combining microbial activity with electrochemical processes to enhance PFAS removal efficiency. Advanced BESs configurations, such as constructed wetland-MFCs, have further demonstrated the potential for enhanced PFAS removal through electrode adsorption and plant uptake. Despite significant progress, challenges remain, including PFAS toxicity, the complexity of environmental matrices, incomplete mineralization, scalability, and public safety concerns. Addressing these issues will require advancements in genetic engineering to develop robust microbial strains, optimization of BESs configurations, and integration with other advanced treatment technologies like advanced oxidation processes. Additionally, refining environmental factors such as pH, temperature, and the presence of humic substances is crucial for maximizing degradation efficiency. Future research should focus on scaling laboratory successes to field-scale applications, developing real-time monitoring tools for degradation processes, and addressing regulatory concerns. Through continuous innovation, biotechnological solutions offer a promising pathway to sustainable and effective PFAS remediation, addressing both environmental and public health concerns.

PMID:40323512 | DOI:10.1007/s10529-025-03593-5

Anal Bioanal Chem. 2025 May 5. doi: 10.1007/s00216-025-05886-0. Online ahead of print.

ABSTRACT

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) possess water-repellent, oil-repellent, and heat-resistant properties, making them widely used in consumer goods and industrial products. However, PFASs have been increasingly associated with health concerns, including reproductive toxicity, endocrine disruption, and thyroid disease. In 2023, the US consumer platform "Mamavation" reported organic fluorine levels ranging from 105 to 20,700 ppm in 18 contact lenses, raising concerns about the potential presence of PFASs in these products. Given the absence of established international testing methods and regulatory limits for PFASs in contact lenses, this study evaluated nine standard international methods, ultimately selecting 49 PFASs as target analytes after eliminating overlaps. To facilitate detection, novel extraction methods were developed for contact lenses and their lens care solutions. Ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was employed for analysis, utilizing an analytical column (Atlantis Premier BEH C18 AX, 1.7 µm, 2.1 × 100 mm) and an isolator column (Atlantis Premier BEH C18 AX, 5 µm, 2.1 × 50 mm) to minimize background interference. Electrospray ionization in combination with multiple reaction monitoring mode enabled rapid analysis within 24 minutes. For contact lenses, the limit of quantification (LOQ) ranged from 1 to 400 ng/g, while for lens care solutions, the LOQ ranged from 0.04 to 0.8 ng/mL. When applied to 12 contact lens samples, the method detected 6:2 FTS (1H,1H,2H,2H-perfluorooctane sulfonic acid) in only one lens care solution at a concentration of 0.087 ng/mL. This study highlights the importance of further investigation into PFAS contamination in contact lenses and the need for international standardization in testing methodologies.

PMID:40323375 | DOI:10.1007/s00216-025-05886-0

Environ Sci Technol. 2025 May 20;59(19):9437-9448. doi: 10.1021/acs.est.4c14790. Epub 2025 May 5.

ABSTRACT

We analyzed blood serum samples from two unique female occupational cohorts - 60 nurses and 40 office workers in San Francisco, CA - using liquid chromatography and high-resolution mass spectrometry (quadrupole time-of-flight). Applying a nontargeted analysis (NTA) approach, we sought to isolate occupationally related chemical exposures that were unique to nurses by flagging features that were different from office workers in abundance (mean; 95th percentile) or detection frequency. Of 9828 negative electrospray ionization (ESI-) and 6898 positive electrospray ionization (ESI+) detected chemical features, 1094 and 938, respectively, were higher in nurses, possibly due to workplace exposures. We deciphered the molecular structures of these chemical features by applying data-dependent acquisition (DDA) and targeted MS/MS approaches to pooled samples from each occupational group, and we annotated them using spectral MS/MS databases in MS-DIAL. Nurses had higher concentrations of 14 chemicals that we identified at Schymanski Level 1 (N = 6) or 2 (N = 8), as well as 20 tentatively identified chemicals without spectra. Several chemicals may be occupationally relevant for nurses, including a PFAS (6:2 fluorotelomer sulfonic acid), tridecanedioic acid, salicylic acid, and the medications acetaminophen and theophylline. To our knowledge, this study is the first to apply NTA to elucidate novel chemical exposures in nurses.

PMID:40324159 | DOI:10.1021/acs.est.4c14790

Risk Anal. 2025 May 5. doi: 10.1111/risa.70047. Online ahead of print.

ABSTRACT

Conflicting information that arises from scientific disagreement poses challenges to effective risk communication. This study explores the impact of conflicting information on risk perception and downstream risk-mitigation behavioral intention and policy support. The research context is PFAS (per- and polyfluoroalkyl substances) contamination. We conducted an online experiment featuring a 2 (information type: conflicting vs. consistent) × 2 (personal relevance: high vs. low) between-subjects factorial design with 1232 American adult participants. Results indicated that exposure to conflicting information dampened risk perception, which subsequently reduced risk-mitigation behavioral intention and policy support, but only when participants perceived the risk from PFAS as less personally relevant. These findings underscore the importance of providing consistent information to the public on emerging environmental risks that bear uncertain health impacts.

PMID:40324946 | DOI:10.1111/risa.70047

bioRxiv [Preprint]. 2025 Apr 15:2025.04.09.647996. doi: 10.1101/2025.04.09.647996.

ABSTRACT

Per-and polyfluoroalkyl substances (PFAS) are ubiquitous contaminants in freshwater ecosystems. Many PFAS are incorporated into food webs, with potential effects on ecological and human health. However, PFAS incorporation into the base of aquatic food webs remains poorly understood. The goal of this study was to quantify the uptake and trophic transfer of both legacy and current use PFAS compounds using a simulated freshwater food chain in a lab setting. Natural periphytic biofilms were placed into trays containing equimolar binary aqueous PFAS mixtures at environmentally relevant concentrations for five days. Following the initial exposure period, newly hatched mayfly larvae were introduced into each tray to feed on periphyton for most of their larval development. The mature larvae were then fed to zebrafish. All water and biota samples contained detectable levels of the tested PFAS. All PFAS were more concentrated in periphyton than in water, and four of six PFAS were further concentrated in mayfly larvae relative to periphyton. PFDA was the most accumulative in all biota. PFAS concentrations in zebrafish were significantly correlated with those in larval mayflies. Assimilation efficiencies in zebrafish were high (>70%) for all compounds. Bioaccumulation of PFAS in periphyton and mayflies was positively correlated with log K _OW and number of carbons.

PMID:40321203 | PMC:PMC12047856 | DOI:10.1101/2025.04.09.647996

Environ Geochem Health. 2025 May 5;47(6):197. doi: 10.1007/s10653-025-02506-9.

ABSTRACT

The Yangtze River is significantly impacted by industrial activities related to per- and polyfluoroalkyl substances (PFAS) in China, posing potential threats to drinking water safety. So far, our knowledge of PFAS occurrence in the river and their fate in the whole drinking water supply systems remains limited. We conducted a comprehensive investigation of PFAS in Jiangsu's drinking water systems, using the target screening method. 12 perfluoroalkyl acids (PFAAs) and 7 emerging PFAS were detected and precisely quantified in the whole treatment process water flows, as well as source water and household tap water with concentrations of 61.34-90.40 ng/L. PFAAs [PFOA (30.26 ng/L), PFBS (23.25 ng/L), PFBA (18.82 ng/L) and PFHxA (16.89 ng/L)] and 8:8 PFPiA (13.63 ng/L) were the dominant pollutants in the low Yangtze River. PFBA (19.92 ng/L), PFBS (15.02 ng/L) and PFOA (11.94 ng/L) were major contaminants in tap water. The powder activated carbon pre-treatment in DWTP-B could remove 21.36-65.84% of long-chain PFAS, especially PFOA. Ozonation achieved slight emerging PFAS removal (3.22-11.06%), while PFAAs concentrations exhibited an increase. Granular active carbon filtration was effective in removing long-chain PFAS, with DWTP-B outperforming DWTP-A. PFSAs (3.12-22.09%) had a better removal than PFCAs (- 0.62 to 19.54%). Infants and children face a moderate health risk of PFAS intake through drinking water, peaking at the age group of 9 months to 1 year (HQ = 2.45). These findings underscore the necessity for improved PFAS removal technologies and stricter regulation of PFAS contamination in the Yangtze River to reduce exposure.

PMID:40325274 | DOI:10.1007/s10653-025-02506-9

J Hazard Mater. 2025 May 2;494:138485. doi: 10.1016/j.jhazmat.2025.138485. Online ahead of print.

ABSTRACT

Epidemiological studies have evinced that particulate matter (PM) is linked to respiratory diseases, but the relationship between the specific constituents of PM and respiratory diseases remains scarce. Here, we evaluated the relationship between PFAS in PM_2.5 with respiratory diseases. In this study, from May 2016 to May 2018, we recruited 131,346 school-aged children and adolescents living in Pearl River Delta, Guangdong Province, China. Participants self-reported the respiratory diseases, including asthma, wheezing, phlegm, cough and rhinitis. Logistic regression and qg-comp models were used to analyze the relationship between PFAS exposure and respiratory diseases. We found several PFAS were significantly associated with higher prevalence of respiratory diseases. For instance, higher quintiles of PFSA exposure (Q2-Q4), as compared to Q1, were associated with greater odds of respiratory diseases: 1.35 (95 %CI: 1.23, 1.48) in Q2, 1.95 (95 %CI: 1.78, 2.14) in Q3 and 2.83 (95 %CI: 2.76, 3.11) in Q4. Furthermore, qg-comp model analysis revealed PFCA as the most important weight in respiratory diseases. Moreover, the effect estimates were higher in boys, older children (>12 years old) and overweight/obesity, indicating the vulnerability of these subpopulations. In summary, exposure to PFAS, a specific PM_2.5 constituent, potentially increases the risk of respiratory diseases among school-aged children and adolescents.

PMID:40319854 | DOI:10.1016/j.jhazmat.2025.138485

Environ Int. 2025 May;199:109460. doi: 10.1016/j.envint.2025.109460. Epub 2025 Apr 22.

ABSTRACT

Chemicals in the EU are mainly regulated based on their intended use. Each legal framework consists of requirements and guidance for hazard- and risk assessment, along with the associated decision processes e.g., registration or authorisation of chemicals for market access in the EU. As a single chemical may have multiple uses, it may be assessed under more than one framework, potentially leading to different assessment outcomes. To address this, the European Commission has introduced the 'one substance, one assessment' approach as part of the Chemicals Strategy for Sustainability. The aims of the approach include streamlining risk assessment processes and reducing duplication of work in assessing the same chemical. This study aimed to map the scope of chemicals subject to assessment in multiple legal frameworks and to illustrate the importance of coordination and communication in chemical assessment processes. This was achieved by identifying chemicals that are either registered or have received specific approval for the EU market, and analysing their presence in different legal frameworks. Our findings showed that almost one-tenth of the substances identified were listed under more than one framework. However, there was a notable lack of coherent chemical identifiers available to accurately identify chemicals across the frameworks. Additionally, we identified the presence of phthalates, bisphenols and PFAS in EU frameworks to illustrate how a group-based approach to chemical assessment could be applied across different legal frameworks.

PMID:40318359 | DOI:10.1016/j.envint.2025.109460